LifeWiki - User contributions [en]

IceNine

2025-05-18T20:11:35Z

Apple Bottom: Turn notes into proper ... well, notes.

{{Glossary}}{{about|a hypothetical unstoppable quadratic growth pattern|a Life-like rule|OCA:Iceballs}}
'''IceNine'''{{refn|group=note|The name is a reference to the [https://en.wikipedia.org/wiki/Ice-nine chemical of the same name] in the novel ''[https://en.wikipedia.org/wiki/Cat's_Cradle Cat's Cradle]'' by [https://en.wikipedia.org/wiki/Kurt_Vonnegut Kurt Vonnegut], with similar properties to the hypothetical pattern. It is not related to [https://en.wikipedia.org/wiki/Ice_IX Ice IX], a metastable form of solid water.}} is [[Dave Greene]]'s name for a hypothetical unstoppable [[quadratic growth]] pattern that expands outward through random [[ash]] at [[speed]] c/137,{{refn|group=note|The coefficient <tt>1/137</tt> is likely a reference to the {{LinkWikipedia|Fine-structure_constant|name=fine-structure constant|nobullet=nobullet|nosuffix=nosuffix}}, a physical constant independent on the system of units in which it is measured. It was thought to be exactly <tt>1/137</tt>, but more accurate measurements have found its denominator to be more precisely <tt>137.035999206</tt>. (See {{OEIS|A005600}}.)}} described as follows in a tongue-in-cheek post in February {{year|2008}}:{{refn|group=note|The dimensions <tt>x {{=}} 2718</tt> and <tt>y {{=}} 4669</tt> of the omitted [[RLE|RLE file]] are likely references to {{LinkWikipedia|E_(mathematical_constant)|name=Euler's number|nobullet=nobullet|nosuffix=nosuffix}} and {{LinkWikipedia|Feigenbaum's_constant|name=Feigenbaum's constant|nobullet=nobullet|nosuffix=nosuffix}} respectively, being the first four digits of each constant.}}

{{Cquote|Aha! You and your intuition have clearly not been exposed to the IceNine Agar, found recently with an alternate-universe oscilloscope:

<pre>#C IceNine seed -- currently this is the smallest sample
#C for which no external conditions have yet been found
#C that prevent long-term quadratic growth
x = 2718, y = 4669, rule = B3/S23
<<<Server notice from fermat.yahoo.com:
11.9MB nonstandard text removed from message
Please notify sender of potential virus threat>>></pre>

Every sufficiently large and ancient B3/S23 universe observed so far turns out to be full of this weird agar, which expands in all directions through random ash at c/137. IceNine seems to absorb blocks and blinkers particularly well, due to a complicated froth of sparks at its front lines -- not generated by glider collisions, but by a lucky accident of the agar's internal structure.

When the expanding front touches an active pattern that it can't immediately annihilate, the pattern "dies back" a short distance at near lightspeed, leaving behind a protective scattering of blocks; behind the blocks the front stabilizes and starts expanding again. Converging IceNine fronts usually cause small diebacks that stabilize as small defects in an apparent quasicrystalline structure.

And before you all ask, my alternate-universe oscilloscope was repossessed by the Outsiders the other day, so unfortunately I can't lend it out. But there didn't seem to be anything but IceNine out there anyway --}}

He went on to further characterize IceNine as follows:

{{Cquote|The IceNine I tried to describe doesn't have a memory per se, any more than a cell's DNA knows the position of every lipid molecule in its cell wall. It's an active, growing agar with lots of edge sparks that just happen to annihilate nearby gliders and still lifes unusually efficiently. Along with several other utterly improbable properties. Basically it's the spacefiller that wins the Survival of the Fittest Award in an infinite Life universe, and it's about as likely as the proverbial tornado in a junkyard building a jumbo jet.}}

It is generally agreed that a pattern exhibiting the characteristics of IceNine cannot exist in [[Conway's Game of Life]], but a formal proof remains elusive. However, mechanisms that a replicator could implement to clear random ash fields with a similar "dying back" process to the one described by Greene to act as a failsafe have been proposed and have been demonstrated to work with greater than 50% odds of success.<ref name="post136948" />

==Notes==
<references group="note" />

==References==
<references>
<ref name="post136948">{{LinkForumThread
|format = ref
|title = Re: Clearing Ash
|p = 136948
|author = mscibing
|date = October 23, 2021
}}</ref>
</references>

==External links==
* {{LinkForumThread|p=293|title=Re: Stable Life?|author=Adam P. Goucher|date=June 13, 2009}}

[[Category:Jokes]]

Non-trivial

2025-05-11T09:04:50Z

Apple Bottom: replace -- with en dash

{{Glossary}}
A [[period]]-''n'' [[oscillator]] is considered '''non-trivial''' if it contains at least one [[cell]] that oscillates at the full period – that is, if it is not made up solely of separate oscillators with smaller periods, but includes a [[spark]] or other reaction that would not occur if all lower-period subpatterns, if any, were separated from each other.

== See also ==
* [[Trivial]]
* [[Omniperiodic]]

==External links==
{{LinkLexicon|filename=lex_n.htm#nontrivial}}

Cellular automaton

2025-05-11T09:04:04Z

Apple Bottom:

{{Glossary}}
{{cleanup}}
'''Cellular automata''' (CA) are a certain class of mathematical objects of which [[Conway's Game of Life]] is an example.

Informally, a cellular automaton consists of:

* A space of cells.
* A set of allowed [[Cell state|states]] for each cell. An assignment of an state to every cell is called a “configuration” or “[[pattern]]” (the first term is more common in mathematical discussion and the later in informal discussions).
* A [[neighbourhood]] which defines which cells are considered to pass information to a given cell.
* A transition rule which specifies how given a cell and the states of its neighbours, a new state is produced.

The state of the cellular automaton evolves in discrete time, with the state of each cell at time ''t''+1 being determined by the state of its neighbourhood at time ''t'' in accordance with the transition rule.

There are some variations on the above definition. It is common to require that there be a [[quiescent]] state (i.e., a state such that if the whole universe is in that state at generation 0 then it will remain so in generation 1). In Conway's Game of Life, the "OFF" state is quiescent, but the "ON" state is not. Other variations allow spaces other than ℤ''n'', neighbourhoods that vary over space and/or time, probabilistic or other non-deterministic transition rules, and so on.

One approach of the study of cellular automata focus on properties that are common to all or many (most often infinitely many) cellular automata, without regard to specific examples. Another approach studies a single or a small finite set of cellular automata for which an explicit description is given.

== Formal definition ==
Let us denote the set of integers by ℤ and the length of any tuple ''x'' by |''x''|. For any tuples of integers ''x'' and ''y'' such that |''x''|=|''y''| we denote their element-wise addition by ''x''+''y''.

A '''cellular automaton''' is a tuple (ℤ''n'',''S'',''N'',''f'') such that the dimension ''n'' is at least 1, the set of states ''S'' is finite, the neighbourhood ''N'' is a tuple of elements of ℤ''n'' and ''f'':''S''|''N''|→''S'' is the transition function.

A '''configuration''' of the cellular automaton (ℤ''n'',''S'',''N'',''f'') is any function ℤ''n''→''S''.

The '''global transition function''' ''F'' of the cellular automaton (ℤ''n'',''S'',''N'',''f'') is a function from configurations to configurations ''F'':(ℤ''n''→''S'')→(ℤ''n''→''S'') such that for any configuration ''c'' and element ''a''∈ℤ''n'' we have ''F''(''c'')(''a'')=''f''(''a''+''N'').

Let ''c'' be a configuration. When the cellular automata is clear from the context, then by ''c''''n'' where ''n'' is a non-negative integer we denote the configuration ''F''''n''(''c'') where ''F'' is the corresponding global transition function.

Let ''c'' and ''c''′ be configurations, then we say that ''c''′ is a '''translation''' of ''c'' if there exist an ''a''∈ℤ''n'' such that for any ''x''∈ℤ''n'' it holds that ''c''′(''a''+''x'')=''c''(''x''). We say that the translation is proper if the condition holds for some ''n''-tuple whose elements are not all 0.

For any configuration ''c'', if there exists a ''n''≥1 such that ''c''''n'' = ''c'' we call ''c'' an '''oscillator'''. If ''c'' is an oscillator and ''n'' is the least positive integer such that ''c''''n'' = ''c'' then we call ''n'' the '''period''' of ''c''. If ''c'' is an oscillator with period 1 then we call ''c'' a '''still life'''. If ''c'' is an oscillator and is not a still life we call ''c'' a '''proper oscillator'''.

A '''glider''' is a configuration ''c'' such that ''c''''n'' is a proper translation of ''c'' for some ''n''>0.

Our definition of cellular automaton is a simple derivative of the one given in [[#Codd_1968|Codd (1968)]]. The only difference in scope is that [[Codd]] only allows grids of dimension 2 and requires the presence of a quiescent state, that is, a state ''v''0 such that ''f''(''v''0,...,''v''0)=''v''0. Moreover, Codd only allows configurations in which finitely many cells are non-quiescent, while our definition of configuration allows any assignment of states to cells.

== Common dimensions and neighborhoods ==
{{Ambox|text=It has been requested that parts of this section be moved into [[neighborhood]].}}
In the approach that studies a small set of automata which are explicitly described the most common space is by far ℤ2. This space can be easily represented in a computer screen or in print, is easy to manipulate, and geometric intuition is applicable. Some explicitly described cellular automata on ℤ1 and ℤ3 have also been studied. A disadvantage of ℤ1 is that information transfer requires many path crossings. In ℤ3 path crossings can be entirely avoided, but is harder to represent than ℤ1 and ℤ2. The most common neighbourhoods of CA in ℤ2 are shown below.

{| style="width: 100%; left-margin: auto; right-margin: auto; border-collapse: collapse;" cellpadding="0"
|- style="vertical-align: top;"
|
{| style="margin: 0 auto; border-spacing: 1em 0;" cellpadding="0"
|- style="vertical-align: top;"
| [[File:von Neumann neighbourhood (range 1).png|frame|none|The [[von Neumann neighbourhood]].]]
| [[File:Emulated hexagonal neighbourhood (range 1).png|frame|none|The [[hexagonal neighbourhood]].]]
| [[File:Moore neighbourhood (range 1).png|frame|none|The [[Moore neighbourhood]].]]
|}
| [[File:Representation of the hexagonal neighbourhood on the square tessellation.png|frame|center|Representation of the hexagonal neighbourhood on the square tessellation.]]
|}

For each dimension ''n''≥1 and radius ''r''≥0 we define the corresponding neighbourhoods:

* The '''generalized von Neumann neighbourhood''' is the set {''x''∈ℤ''n''|(MAX0≤''i''≤''n''-1|''x''''i''|)<''r''}.
* The '''generalized Moore neighbourhood''' is the set {''x''∈ℤ''n''|(Σ0≤''i''≤''n''-1|''x''''i''|)<''r''}.
* The '''Euclidean neighbourhood''' is the set {''x''∈ℤ''n''|(√Σ0≤''i''≤''n''-1''x''''i''2)<''r''}.

See ''[[Gallery of neighbourhoods]]'' illustrations of some instances in ℤ2.

The third proper regular tiling of two-dimensional space, the [[triangular neighbourhood|triangular tiling]],<ref name="post43653" /> has been investigated; it can be simulated on the square grid using 4 states that divide each cell into two right triangles.<ref>{{cite web|url=https://github.com/gollygang/ruletablerepository/wiki/TheRules|title=The Rules|work=Golly Rule Table Repository|author=Tim Hutton|date=June 28, 2015|accessdate=August 30, 2017}}</ref> It can be divided into at least two major neighbourhoods, the [[triangular Moore neighbourhood]] and [[triangular von Neumann neighbourhood]].

Three-dimensional rules use the [https://en.wikipedia.org/wiki/Cubic_honeycomb cubic honeycomb], which gives rise to many potential neighbourhoods, such as the cubic Moore and cubic Von Neumann neighbourhoods, among others.

Four-dimensional rules most commonly use the [https://en.wikipedia.org/wiki/Tesseractic_honeycomb tesseractic honeycomb] (with a tesseractic Moore and tesseractic von Neumann neighbourhood). While four-dimensional space also admits the [https://en.wikipedia.org/wiki/16-cell_honeycomb 16-cell honeycomb] and [https://en.wikipedia.org/wiki/24-cell_honeycomb 24-cell honeycomb], these do not seem to have been used as of yet.

Irregular [https://en.wikipedia.org/wiki/tesselation| tesselations], such as the [https://en.wikipedia.org/wiki/Cairo_pentagonal_tiling Cairo pentagonal] tesselation, have been investigated.

== Generalizations and topological characterization ==
Our definition is enough to describe most of the cellular automata in which explicitly described configurations are studied. In particular it handles as expected the elementary cellular automata, CA on the Euclidean square tessellation (including all life-like CA and all non-totalistic CA) and the Euclidean hexagonal tessellation. Furthermore, CA on the Euclidean triangular tessellation can be handled when proper care is taken. However, there exist objects which are cellular automata according to our informal description, but can not be defined as such in our formal definition. An example is cellular automata in hyperbolic tessellations ([[#Margenstern_2013|Margenstern, 2013]]). A very general definition of cellular automata is given in [[#Moriceau_2011|Moriceau (2011)]] and a further generalization is given in [[#Wacker_2016|Wacker (2016)]]. Interestingly, Wacker's definition uses amenable groups. Both amenable groups and cellular automata were introduced by the same man: [[John von Neumann]].

A remarkable result, the '''Curtis-Hedlund-Lyndon-Richardson (CHLR) theorem''', relates cellular automata theory with topology and dynamical system theory. An informal statement is given as follows: Let the set of states be given the discrete topology and the configuration space be given the Tikhonov topology; then the global transition functions of the cellular automata over the configuration space are exactly those functions which are continuous and commute with the translations of the cellular space. In particular, the CHLR theorem holds for our definition of CA. Informally we state that the CHLR theorem holds for definitions of CA where the set of states is required to be finite, but if the set of states is allowed to be infinite, the set of allowable neighborhoods must be expanded or a further constraint must be imposed on continuous functions so that an analogous result holds ([[#Ceccherini-Silberstein_2010|Ceccherini-Silberstein 2010]]; [[#Sobottka_2015|Sobottka 2015]]). Generally when a novel definition of cellular automaton is presented a corresponding version of the CHLR theorem is proved in the same treatise.

The CHLR theorem was demonstrated independently by [[#Hedlund_1969|Hedlund (1969)]] (in this paper credit is given to Curtis and Lyndon in addition to the author) and [[#Richardson_1972|Richardson (1972)]]. Neither of these papers use the term “cellular automaton”. Nonetheless the systems they study are, respectively, 2-dimensional deterministic cellular automata and ''n''-dimensional non-deterministic cellular automata.

=== Block cellular automata ===
{{main|Block cellular automaton}}

In the above definitions of cellular automata, the transition function takes the state of a set of possibly many cells and gives the next state for a single cell. A block cellular automaton differs in that the universe is partitioned into non-overlapping blocks of finite size, and the transition rule is applied to a whole block at a time rather than a single cell. A motivation to study block cellular automata is the ease with which reversible global transition functions can be generated.

== Self-replicating configurations ==
Informally, a configuration that creates a copy of itself after some number of generations is called a [[replicator]].

John von Neumann investigated the possibility of building a self-replicating machine. He originally considered a mechanical approach, but decided that this was too hard to control. With the help of [[Stanislaw Ulam]], he designed a new mathematical abstraction, the cellular automaton, in order to create a [[replicator]]. His CA was made in the late 1940s and is complex. It operates on the [[Von Neumann neighbourhood]] (a cell and its four orthogonally connected neighbours), and has 29 states. It is described in [[#von_Neumann_1966|von Neumann, Burks (1966)]].

Subsequent to the von Neumann's cellular automaton new cellular automata have been produced capable of self-replication and universal computation with fewer states and using the same (von Neumann) neighborhood. Results include [[#Codd_1968|Codd (1968)]] with 8 states, [[#Banks_1971|Banks (1971)]] with 4 states and [[#Serizawa_1987|Serizawa (1987)]] with 3 states. Prior to the discovery of Life's [[0E0P metacell]] in 2018, Serizawa's CA was the simplest (in terms of neighborhood size×number of states) cellular automaton known to have a non-trivial replicator.

[[#Langton_1984|Langton (1984)]] constructed a cellular automaton and a replicator. His cellular automaton is a simplification of Codd's. However, Langton's CA was not intended to support universal computation. The simplicity of the configuration is possible because of a novel method of self-replication. The replicator consists of a loop with circulating cell states that encode instructions to construct a new arm, then turn 90° and repeat until a new loop is formed. The new loop is then filled with the same circulating information and the connection between it and the loop that generated it is severed. The parent loop continues to build copies until no more space is available, then it becomes a still life. Later variants of the loop added construction capabilities to it, and the most advanced versions granted it properties akin to a living organism, including a finite "lifespan", an approximation of evolution via natural selection, and sexual reproduction.

[[#Nehaniv_2002|Nehaniv (2002)]] presented a method that allows the transformation of conventional (synchronous) cellular automata to an equivalent asynchronous cellular automata (a case not covered by our definition above). In the same paper, a self-reproducing configuration is presented which is based on the described procedure applied to Langton's CA.

Conway's Game of Life is known to be universal, with 2 states and the Moore neighbourhood. Conway did not design Life for this purpose, unlike von Neumann's, Codd's, Banks' and Serizawa's rules, but he did deliberately choose a set of rules known to exhibit sufficiently complex behavior that self-replication was likely to be possible. In other words, when the rules of Life were first chosen, it was not a foregone conclusion that replicators would be constructible -- but it can't be said that the existence of replicators in the rule is purely coincidental.

The [[Spartan universal computer-constructor]] could replicate, given a sufficient program tape. The [[Gemini]] spaceship constructs a complete copy of its own circuitry, but is not considered to be a replicator because its instruction tape is never duplicated. Between 2010 and 2017 much more efficient construction mechanisms have been developed that can be used for self-replication, but to date only a limited one-dimensional example has actually been completed (the [[linear propagator]]).

=== Formal definition ===
There are several possible non-equivalent definitions of self-replicators. [[#Moore_1962|Moore (1962)]] proposed a simple definition which does not attempt to exclude trivial cases (although Moore wrote “self-reproduction”, we assume that it synonymous with “self-replication”). However, his definitions of self-replicator is limited to the same cellular automata and configurations allowed by the definition of [[#Codd_1968|Codd (1968)]]. Our definition is a slight generalization of Moore's definition to cover all the configurations allowed by our definition.

Not all of the self-replicators mentioned above meet our formal definition. Langton's self-replicating loop and the [[OCA:HighLife/Replicator|classical HighLife replicator]] meet our definition. Typically, a configuration does not meet our definition if each copy generates only one "child" copy of itself, and does not return to its initial state after finishing construction of the child copy.

A slight complication not covered below is the case of a high-period replicator pattern that creates its child copies in a different phase from the parent. For example, a replicator may contain oscillating components such as a moving "tape" of gliders for information storage. Parent and child copies of the configuration may not match exactly at any given time -- but a future state of the child copy will precisely match the current state of the parent copy, and vice versa.

It seems reasonable to consider such parent/child pairs to be valid copies of each other for the purposes of the definitions below, even if they are not phase-matched. In most cases it can be shown that after a sufficient number of replication cycles have passed, an arbitrarily large number of phase-matched descendants of a parent pattern will inevitably be present.

'''Definition:''' Let (ℤ''n'',''S'',''N'',''f'') be a cellular automaton. Let ''c'' be a configuration such that for some ''s''∈''S'' the set ''X''={''a''∈ℤ''n''|''c''(''a'')≠''s''} is finite. We say that ''c'' is a '''finite configuration''', ''s'' is a '''background state''' of ''c'' and ''X'' is a '''support''' of ''c''.

'''Theorem:''' Let ''c'' be a finite configuration, then there is a unique background state and support of ''c''.

: Let ''v'' and ''v''′ be background states of ''c''. Let ''X'' be the set of all cells ''a'' such that ''c''(''a'')≠''v'' and respectively for ''X''′ and ''v''′. The set ℤ''n''\(''X''∪''X''′) is non-empty because ℤ''n'' is infinite and ''X''∪''X''′ is finite. Let ''x''∈ℤ''n''\(''X''∪''X''′). By the properties of set union and complement we have ''x''∈ℤ''n''\''X'' and ''x''∈ℤ''n''\''X''′; by definition of ''X'' and ''X''′ we have ''x''=''v'' and ''x''=''v''′; therefore ''v''=''v''′. Again from the definition of ''X'' and ''X''′ it follows that ''X''=''X''′.

'''Definition:''' Let ''c'' be a finite configuration. We write bg(''c'') for the background state of ''c'' and we write su(''c'') for the support of ''c''.

'''Definition:''' Let ''c'' and ''c''′ be finite configurations such that bg(''c'')=bg(''c''′). If su(''c'')∩su(''c''′)=∅ we say that ''c'' is '''disjoint''' from ''c''′. If su(''c'')⊂su(''c''′) and for all ''a''∈su(''c'') we have ''c''(''a'')=''c''′(''a'') then we say that ''c''′ '''contains''' ''c''.

'''Definition:''' Let ''c'' and ''c''′ be configurations. We say that ''c''′ '''contains at least''' ''n'' copies if ''c'' if there exist a set ''X'' of pairwise disjoint translations of ''c'' and for each ''x''∈''X'', ''c'' contains ''x''.

'''Definition:''' A configuration ''c'' is called a ''self-replicator'' if for any ''n''≥1 there exist a ''t''≥0 such that ''c''''t'' contains at least ''n'' disjoint copies of ''c''.

'''Definition:''' Let ''c'' and ''c<nowiki/>'' be a configuration. Let ''n''≥0 be an integer. If ''c''′ contains at least ''n'' copies of ''c'' and for any integer ''k''>''n'' it is not the case that ''c''′ contains at least ''k'' copies of ''c'' then we say that ''c''′ '''contains exactly''' ''n'' copies of ''c''.

== Life-like cellular automata ==
{{main|Life-like cellular automaton}}

A cellular automaton is said to be ''Life-like'' if it meets the following four criteria:

* It has two dimensions (i.e., ''n''=2).
* It has two states, usually called OFF and ON (i.e., |''S''|=2).
* It uses the Moore neighbourhood.
* The new state of a cell in the next [[generation]] can be expressed as a function of the number of cells in its neighbourhood that are in the ON state and the cell's own state; that is, the rule is ''outer totalistic'' (also called ''semitotalistic'').

This class of cellular automata is named for [[Conway's Game of Life]], the most famous cellular automaton, which meets all four criteria above.

==Cyclic cellular automaton==
'''Cyclic cellular automata''' are a class of cellular automata commonly known for producing spiral patterns.

==Partitioned cellular automaton==
'''Partitioned cellular automata''' ('''PCA''') are a class of cellular automata investigated due to their capability for reversibility. They have been researched on square and triangular grids.

==Rock-paper-scissors cellular automaton==
'''Rock-paper-scissors cellular automata''' are a class of cellular automata based on the classic game of rock-paper-scissors as well as variations thereof.<ref>https://softologyblog.wordpress.com/2018/03/23/rock-paper-scissors-cellular-automata/</ref>

==See also==
* {{CategoryLink|Cellular automata}}
* {{CategoryLink|Lists of rule tables}}
* [[Vanishing dual]]

==References==
<references>
<ref name="post43653">{{LinkForumThread
|format = ref
|title = Re: Thread for basic questions
|p = 43653
|author = Brian Prentice
|date = May 20, 2017
}}</ref>
</references>

===Books and articles===
*Banks, E. R. (1971) [http://www.bottomlayer.com/bottom/banks/banks_thesis_1971.pdf ''Information processing and transmission in cellular automata''].
*Ceccherini-Silberstein, T.; Coornaert, M. (2010) ''Cellular Automata and Groups''. DOI: 10.1007/978-3-642-14034-1. ISBN: 978-3-642-14033-4, 978-3-642-14034-1.
*Codd, E. F. (1968) ''Cellular Automata''. No ISBN. WorldCat OCLC number: [https://www.worldcat.org/title/cellular-automata/oclc/637978742 637978742].
*Hedlund, G. A. (1969) ''Endomorphisms and Automorphisms of the Shift Dynamical System''. DOI: 10.1007/BF01691062.
*Langton, C. G. (1984) ''Self-reproduction in cellular automata''. DOI: 10.1016/0167-2789(84)90256-2.
*Margenstern, M. (2013) ''Small Universal Cellular Automata in Hyperbolic Spaces: A Collection of Jewels''.
*Moore, E. F. (1962) ''Machine models of self-reproduction'' in ''Mathematical Problems in the Biological Sciences''. DOI: 10.1090/psapm/014/9961.
*Moriceau, S. (2011) ''Cellular automata on a ''G''-set''. arXiv: [https://arxiv.org/abs/1105.5335 1105.5335 [math.DS<nowiki>]</nowiki>].
*Nehaniv, C. E. (2002) [http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.7.2073&rep=rep1&type=pdf ''Self-Reproduction in Asynchronous Cellular Automata''] in ''Proceedings 2002 NASA/DoD Conference on Evolvable Hardware''. DOI: 10.1109/eh.2002.1029854.
*Richardson, D. (1972) ''Tessellation with Local Transformations''. DOI: 10.1016/S0022-0000(72)80009-6.
*Serizawa, T. (1987) ''Three-State Neighbor Cellular Automata Capable of Constructing Self-Reproducing Machines''. DOI: 10.1002/scj.4690180404.
*Sobottka, M.; Gonçalves, D. (2015) ''A note on the definition of sliding block codes and the Curtis-Hedlund-Lyndon Theorem''. arXiv: [https://arxiv.org/abs/1507.02180 1507.02180 [math.DS<nowiki>]</nowiki>].
*von Neumann, J.; Burks, A. W. (1966) [https://archive.org/download/theoryofselfrepr00vonn_0/theoryofselfrepr00vonn_0.pdf ''Theory of Self-Reproducing Automata'']. No ISBN. WorldCat OCLC number: [https://www.worldcat.org/title/theory-of-self-reproducing-automata/oclc/7298386 7298386].
*Wacker, S. (2016) ''Cellular Automata on Group Sets and the Uniform Curtis-Hedlund-Lyndon Theorem''. DOI: 10.1007/978-3-319-39300-1_15. In ''Cellular Automata and Discrete Complex Systems. AUTOMATA 2016.''

== External links ==
*{{LinkWikipedia|Cellular_automaton|name=Cellular automaton}}
*{{LinkWikipedia|Cyclic_cellular_automaton|name=Cyclic cellular automaton}}
*{{LinkWikipedia|Rock_paper_scissors|name=Rock paper scissors}}
*{{LinkForumThread|f=11|t=4098|title=Partitioned Cellular Automata}}
*{{LinkMirek|ca_rules.html|title=Cellular automata rules lexicon}}
*{{LinkLexicon|lex_c.htm#cellularautomaton}}
*{{LinkMathworld|CellularAutomaton.html|pagename=Cellular Automaton}}
*{{LinkMathworld|TotalisticCellularAutomaton.html|pagename=Totalistic Cellular Automaton}}
*[https://github.com/gollygang/ruletablerepository Golly Rule Table Repository]

Cell state

2025-05-11T09:03:54Z

Apple Bottom:

{{Glossary}}
A '''cell state''' or '''cellstate''' is one of several states that a cell can be in. [[Conway's Game of Life|Life]], [[outer-totalistic]] rules, [[isotropic non-totalistic rule]]s, [[MAP rule]]s, and [[Larger than Life]] rules have two cell states: "on" and "off" (or "alive" and "dead"). Others, such as [[Generations]] and [[deficient rule]]s, as well as {{rl|LifeHistory}}, variants of Life such as [[Immigration]] and {{rl|Symbiosis}}, and circuitry rules such as {{rl|WireWorld}}, are [[multistate rule]]s.

It is common to require that there be at least one [[quiescent]] state (i.e., a cell state such that if the whole [[universe]] is in that state at generation 0 then it will remain so in generation 1). In Conway's Game of Life, the "off" state is quiescent, but the "on" state is not. In {{rl|Day & Night}}, both states have this property; the same is true for other [[self-complementary]] non-[[strobing]] rules. In a strobing rule, neither the "off" state nor the "on" state is quiescent.

Multistate rules have each cell state defined by an integer from 0 to the number of states minus one, where 0 is the background state. Some multistate rules clearly have some "on" states and "off" states. For example, Generations rules have state 1 as the only "on" state, in Immigration and [[QuadLife]], every state except the background is "on", and in LifeHistory and {{rl|LifeSuper}}, odd-numbered states are "on". Other rules have no clear distinction between on states and off states.

Strobing rule

2025-05-11T09:03:02Z

Apple Bottom:

{{Glossary}}
A two-state [[Cellular automaton|rule]] is said to be '''strobing''' {{iff}} neither of the two [[cellstate]]s is [[quiescent]]. For example, a strobing [[Life-like cellular automaton]] contains B0 (dead cells get born if they have zero live neighbors) but not S8 (live cells do not survive if they have eight live neighbors). In strobing rules, the entire [[universe]] will "light up" (get born) and die again in successive alternate generations, creating a visual "strobing" effect.{{refn|group=note|This effect may not actually be rendered by software supporting such rules, e.g. [[Golly]].}}

==Strobing duals of self-complementary rules==
[[Self-complementary]] outer-totalistic rules (i.e. [[Life-like cellular automaton|Life-like cellular automata]] that are invariant under [[black/white reversal]]) necessarily include precisely one of B0 and S8. Applying the transformation below to a self-complementary rule with S8 but not B0 yields a rule with B0 but not S8, i.e. a strobing rule in the above sense. This rule is called the '''equivalent strobing rule''' or '''strobing dual''' of the original rule.

Applying the "strobing rule" transformation a second time yields the original rule again, so each (non-strobing) self-complementary rule and its equivalent strobing rule form a pair. As there are exactly 29 = 512 self-complementary outer-totalistic rules, and each equivalent strobing rule is itself self-complementary, there are exactly 28 = 256 such pairs.

There are instead 251 self-complementary [[isotropic non-totalistic rule]]s, with equivalence classes of quartets formed by the strobing dual and [[checkerboard dual]].

Patterns evolve identically in the strobing and non-strobing versions of a self-complementary rule, except that in the strobing version, every other generation is [[black/white reversal|inverted]].

===Determining the equivalent strobing rule of a self-complementary rule===
A given self-complementary rule's strobing dual is determined in the same way as its black/white reversal, except that its original B and S conditions are not negated.

That is to say, to determine the strobing version of a given rule:

# Subtract each condition in B and S from 8, yielding B′ and S′.
# The equivalent strobing rule of B/S is S′/B′.

For self-complementary rules, this can be reduced to the following, easier method:

# Negate each condition in B and S, yielding B′ and S′.
# The equivalent strobing rule of B/S is B′/S′.
Using the latter algorithm, it is easy to see that the [[rule integer]]s of a rule and its strobing equivalent's always add up to 262143 (218 - 1), which is also the number of possible range-1 outer-totalistic rules (minus one).

====Example====
Applying the first method to the rule B356/S014678, we have:

# B = 356; S = 014678
# B′ = 235; S′ = 012478

Or, using the second method:

# B = 356; S = 014678
# B′ = 012478; S′ = 235

Therefore, the equivalent strobing rule of B356/S014678 is B012478/S235.

Note that similarly to black/white reversal, when converting isotropic non-totalistic rules written in [[Hensel notation]], B4 and S4 conditions are not only subtracted from 8 (which would map them to themselves), but must be considered on a per-letter basis. After the negation, a mapping (<tt>M</tt>) is enacted that swaps elements of the pairs (4c,4e), (4i,4t), (4n,4r), (4y,4j), and (4q,4w) with their partners, but preserves 4k, 4a, and 4z.

==Equivalent alternating rules of strobing rules==
Some programs, such as Golly, don't simulate strobing rules directly, but [[Alternating rule|alternate]] between two equivalent non-strobing ones on even and odd generations.<ref>[http://golly.sourceforge.net/Help/Algorithms/QuickLife.html {{filename|Help/Algorithms/QuickLife}}]</ref> For even generations, invert all conditions (ie. the strobing rule followed by a cellwise NOT), and for odd ones, subtract conditions' outer-totals from 8 (applying map <tt>M</tt> to B4 and S4 ones), and swap the birth and survival ones (ie. the black/white reversal of the strobing rule).

If followed on a non-strobing rule, this will (unusefully) return an alternating pair of equivalent strobing rules.

==Notes==
<references group="note" />

==See also==
* [[List of strobing rules]]

==References==
<references />

[[Category:Dualities]]
[[Category:Strobing rules| ]]

Quiescent

2025-05-11T09:02:56Z

Apple Bottom: New glossary, because it's used elsewhere

{{Glossary}}
A [[cell state]] of a [[cellular automaton]] is said to be '''quiescent''' if the whole universe, when initialized to this state at generation 0, will remain in the same state in generation 1.

Chapman-Greene construction arm

2024-04-21T07:26:13Z

Apple Bottom:

{{Glossary}}
The '''Chapman-Greene Construction Arm''' is a programmable [[construction arm]] built in May 2004 by [[Paul Chapman]] and [[Dave Greene]].<ref name="post141232" />

In May 2022, [[Adam P. Goucher]] rebuilt the Chapman-Greene Construction Arm using up-to-date [[spartan]] technology; the resulting construction arm is known as the [[Goucher-Grankovskiy construction arm]].<ref name="post145133" />

==Method==
[[Signal]]s prompt the [[universal constructor]] to pull the construction arm's [[elbow]] closer, push it farther away, or shoot a glider of either color sideways from the elbow's current position. The choice of operations--PUSH, PULL, the two FIRE recipes, or a SHUT DOWN signal--is made by reading a static tape where one to five 1's ([[boat]]s) are stored in unary, separated by zeroes ([[block]]s).

==See also==
* [[Goucher-Grankovskiy construction arm]]
* [[Universal constructor]]
* [[Gemini]]
* [[Oblique spaceship]]

==References==
<references>
<ref name="post141232">{{LinkForumThread
|format = ref
|title = Re: Thread for basic questions
|p = 141232
|author = Dave Greene
|date = February 4, 2022
}}</ref>
<ref name="post145133">{{LinkForumThread
|format = ref
|title = Re: Chapman-Greene construction arm
|p = 145133
|author = Calcyman (Adam P. Goucher)
|date = May 5, 2022
}}</ref>
</references>

[[Category:Universal construction]]

Goucher-Grankovskiy construction arm

2024-04-21T07:26:03Z

Apple Bottom:

{{Glossary}}
The '''Goucher-Grankovskiy Construction Arm''' is a programmable [[construction arm]], a rebuilt version of the classic [[Chapman-Greene construction arm]] using up-to-date [[spartan]] technology, created by [[Adam P. Goucher]] in May 2022.<ref name="post145133" />

==See also==
* [[Chapman-Greene construction arm]]
* [[Universal constructor]]
* [[Gemini]]
* [[Oblique spaceship]]

==References==
<references>
<ref name="post145133">{{LinkForumThread
|format = ref
|title = Re: Chapman-Greene construction arm
|p = 145133
|author = Calcyman (Adam P. Goucher)
|date = May 5, 2022
}}</ref>
</references>

[[Category:Universal construction]]

Goucher-Grankovskiy construction arm

2024-04-21T07:25:23Z

Apple Bottom: Initial stub.

{{Glossary}}
The '''Goucher-Grankovskiy Construction Arm''' is a programmable [[construction arm]], a rebuilt version of the classic [[Chapman-Greene construction arm]] using up-to-date [[spartan]] technology, created by [[Adam P. Goucher]] in May 2022.<ref name="post145133" />

==See also==
* [[Chapman-Greene construction arm]]
* [[Universal constructor]]
* [[Gemini]]
* [[Oblique spaceship]]

==References==
<references>
<ref name="post145133">{{LinkForumThread
|format = ref
|title = Re: Chapman-Greene construction arm
|p = 145133
|author = Dave Greene
|date = May 5, 2022
}}</ref>
</references>

[[Category:Universal construction]]

Chapman-Greene construction arm

2024-04-21T07:21:19Z

Apple Bottom:

{{Glossary}}
The '''Chapman-Greene Construction Arm''' is a programmable [[construction arm]] built in May 2004 by [[Paul Chapman]] and [[Dave Greene]].<ref name="post141232" />

In May 2022, [[Adam P. Goucher]] rebuilt the Chapman-Greene Construction Arm using up-to-date [[spartan]] technology; the resulting construction arm is known as the [[Goucher-Grankovskiy construction arm]].<ref name="post145133" />

==Method==
[[Signal]]s prompt the [[universal constructor]] to pull the construction arm's [[elbow]] closer, push it farther away, or shoot a glider of either color sideways from the elbow's current position. The choice of operations--PUSH, PULL, the two FIRE recipes, or a SHUT DOWN signal--is made by reading a static tape where one to five 1's ([[boat]]s) are stored in unary, separated by zeroes ([[block]]s).

==See also==
* [[Goucher-Grankovskiy construction arm]]
* [[Universal constructor]]
* [[Gemini]]
* [[Oblique spaceship]]

==References==
<references>
<ref name="post141232">{{LinkForumThread
|format = ref
|title = Re: Thread for basic questions
|p = 141232
|author = Dave Greene
|date = February 4, 2022
}}</ref>
<ref name="post145133">{{LinkForumThread
|format = ref
|title = Re: Chapman-Greene construction arm
|p = 145133
|author = Dave Greene
|date = May 5, 2022
}}</ref>
</references>

[[Category:Universal construction]]

Pattern of the Year

2024-04-21T07:19:29Z

Apple Bottom: 2023: stalled? or ongoing?

The '''Pattern of the Year''' ('''POTY''') competition is held each year on the [[ConwayLife.com]] forums. Users are invited to submit interesting and noteworthy patterns, their own or others'; following discussion, a final list is then curated, and a public vote held. There are only two hard and fast rules: patterns must have been discovered in the year in question; and patterns must work in B3/S23 ([[Conway's Game of Life]]).

{| class="wikitable"
! Contents
|-
| [[#Summary|Summary]]{{br}}[[#Results by year|Results by year (details)]] {{br}} [[#See also|See also]]{{br}}[[#References|References]]
|}

==Summary==

{| class="wikitable"
|-
! Year{{br}}(click for details)
! First place
! Second place
! Third place
|-
| <center>[[#2022|2022]]</center> || [[Unique father problem|Unsynthesizable and limited-ancestor objects]] [[reverse caber tosser|Explicit 15-glider reverse caber tosser]]† || || [[Self-synthesizing glide-reflecting loopship]]
|-
| <center>[[#2021|2021]]</center> || [[Self-synthesizing oblique loopship]] || [[Reflectorless rotating oscillator]] || [[Traffic stop]]{{br}}[[DOGun SaGaQR]]†
|-
| <center>[[#2020|2020]]</center> || [[Bandersnatch]]{{br}}[[Speed Demonoid]]† || || Spaceship glider syntheses
|-
| <center>[[#2019|2019]]</center> || [[David Hilbert]] || [[Spider]] synthesis || [[Scholar]]
|-
| <center>[[#2018|2018]]</center> || [[Sir Robin]] || [[0E0P metacell]] || [[Reverse caber-tosser]]
|-
| <center>[[#2017|2017]]</center> || [[2-engine Cordership]] || [[Tanner's p46]] || [[Stable pulse-divider]]s
|-
| <center>[[#2016|2016]]</center> || [[Caterloopillar]]s || [[Copperhead]] || [[Grandfather problem|Grandfather-less Pattern]]
|-
| <center>[[#2015|2015]]</center> || [[Syringe]] || [[Simkin glider gun]] || [[Demonoid]]s
|-
| <center>[[#2014|2014]]</center> || [[Waterbear]] || [[Centipede]] || [[Half-baked knightship]]
|-
| <center>[[#2013|2013]]</center> || [[Snark]] || [[Loafer]] || [[CC semi-Snark]]{{br}}[[Linear propagator]]†
|-
| <center>[[#2012|2012]]</center> || [[Statorless p3]] || Direct stable Herschel duplicator || Period-4 90-degree reflector{{br}}[[37P4H1V0]]†
|-
| <center>[[#2011|2011]]</center> || [[Fully universal Turing machine]]{{br}}[[Lobster (spaceship)|Lobster]]† || || [[Garden of Eden 6]]
|-
| <center>[[#2010|2010]]</center> || [[Gemini]] || [[Phi calculator]] || [[c/5 diagonal rake]]
|-
| <center>2004‡</center> || [[Caterpillar]]‡<ref name="post2115" /> || ||
|-
|}

‡ Result of informal consensus rather than formal competition

† Patterns were tied on number of votes

==Results by year==
{| class="wikitable"
! Contents
|-
|[[#2023|2023]] [[#2022|2022]] [[#2021|2021]] [[#2020|2020]] [[#2019|2019]] [[#2018|2018]] [[#2017|2017]] [[#2016|2016]] [[#2015|2015]] [[#2014|2014]] [[#2013|2013]] [[#2012|2012]] [[#2011|2011]] [[#2010|2010]]
|}

===2023===
[https://conwaylife.com/forums/viewtopic.php?f=2&t=6299 Entries] • ''Voting'' • ''Results''

===2022===
[https://conwaylife.com/forums/viewtopic.php?f=2&t=5910#p155456 Entries] • [https://conwaylife.com/forums/viewtopic.php?f=2&t=6050 Voting] • [https://conwaylife.com/forums/viewtopic.php?p=166268#p166268 Results]

In the {{year|2022}} competition, users were able to vote on as many patterns as they wish, awarding up to five stars to each one. [[Oscar Cunningham]], [[Dave Greene]], and [[Matthias Merzenich]] helped to organize the nominations, and [[b3s23love]] volunteered to see the project through to completion.

(Note: A collection of links to many of these discoveries can be found in [https://conwaylife.com/forums/viewtopic.php?p=162372#p162372 this post] in the nominations thread.)

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Stars
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| =1 || 173 || Unsynthesizable and limited-ancestor objects || [[Ilkka Törmä]] and [[Ville Salo]] || [https://conwaylife.com/wiki/Unique_father_problem] [https://conwaylife.com/wiki/Unsynthesizable_oscillator_1] [https://conwaylife.com/forums/viewtopic.php?p=139854#p139854] [https://conwaylife.com/wiki/American%20Dream]
|- class="expand-child"
| colspan="5" | These discoveries include an [https://conwaylife.com/wiki/Unique_father_problem unsynthesizable still life] and [https://conwaylife.com/wiki/Unsynthesizable_oscillator_1 unsynthesizable p2 oscillator], both based on "self-forcing" [[agar]]s, a [https://conwaylife.com/forums/viewtopic.php?p=139854#p139854 generalized solution to the grandfather problem] (patterns that have n-tick predecessors but no (n+1)-tick predecessors), and [[American Dream]], a finite pattern with an infinite-population [[predecessor]] but no finite-population [[predecessor]].
|-
| =1 || 173 || Explicit 15-glider reverse caber tosser || [[Daniel Vargas]], [[Adam P. Goucher]], [[Pavel Grankovskiy]], [[Simon Ekström]], [[Dave Greene]], [[AlbertArmStain]], [[Oscar Cunningham]], [[Chris Cain]], [[dani]], and [[Goldtiger997]] || [https://biggieblog.com/building-arbitrary-life-patterns-in-15-gliders] [https://conwaylife.com/wiki/Reverse_caber-tosser]
|- class="expand-child"
| colspan="5" | A concrete construction demonstrating that any [[glider synthesis]] can be reduced to use just 15 [[glider]]s. The number of gliders was also reduced from its previous value of 17.
|-
| data-sort-value="3" | 3 || 129 || Self-synthesizing glide-reflecting loopship || [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=142538#p142538] [https://conwaylife.com/wiki/Self-synthesizing_oblique_loopship#Self-synthesizing_glide-reflecting_loopship]
|- class="expand-child"
| colspan="5" | A [[pattern]] made entirely of gliders that synthesises a reflected and translated copy of itself. Thus it is an [[orthogonal]] [[spaceship]] travelling at a [[speed]] of 30985960c/144171206.
|-
| data-sort-value="4" | 4 || 127 || The Great Oscillator Discovery Project || [[David Raucci]], [[Mitchell Riley]], [[Luke Kiernan]], [[iNoMed]], et al. || [https://conwaylife.com/wiki/User:Entity_Valkyrie_2/2022_oscillator_stamp]
|- class="expand-child"
| colspan="5" | This project continued 2022's increased focus on the discovery of new [[oscillator]]s, partially to work toward filling in the remaining unknown oscillator periods to finally prove Life to be [[omniperiodic]].
|-
| data-sort-value="5" | 5 || 126 || [[Speed Orthogonal Loopship]] || [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=153452#p153452]
|- class="expand-child"
| colspan="5" | A pattern made entirely of [[XWSS]]es that synthesises a reflected and translated copy of itself. It travels orthogonally and is adjustable so that its speed can become arbitrarily close to [[c/2]]. Its population is much less than that of the [[Speed Orthogonoid]].
|-
| data-sort-value="5" | 5 || 126 || [[Raucci's p38]] || [[David Raucci]], [[Jason Summers]], and [[cvojan]] || [https://conwaylife.com/forums/viewtopic.php?p=140183#p140183]
|- class="expand-child"
| colspan="5" | The first known oscillator with period 38, made by adding copies of cvojan's [[traffic stop]] as [[fencepost]]s for a known [[wick]] by Jason Summers.
|-
| data-sort-value="7" | 7 || 124 || [[Speed Orthogonoid]] || [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=143667#p143667]
|- class="expand-child"
| colspan="5" | An [[adjustable spaceship]] capable at travelling orthogonally at any speed less than c/2.
|-
| data-sort-value="8" | 8 || 122 || [[Engineered diehard]]s || [[Dean Hickerson]], [[Pavel Grankovskiy]], [[toroidalet]], and [[Tanner Jacobi]] || [[Engineered diehard]]s
|- class="expand-child"
| colspan="5" | A series of diehard patterns with increasingly long lifespans, culminating in the discovery of a pattern that starts in a [[bounding box]] of area 9990, and yet lives for more than 10^10^10^10^10^10^10^10^10^10^10^10^10^10^10 generations before dying out completely.
|-
| data-sort-value="9" | 9 || 120 || Lisp in Life || Hikaru Ikuta || [https://woodrush.github.io/blog/posts/2022-01-12-lisp-in-life.html]
|- class="expand-child"
| colspan="5" | A Lisp interpreter implemented in Conway’s Game of Life, using technology similar to the Quest for Tetris project. This is the first implementation of a standardized high-level programming language inside Conway’s Game of Life.
|-
| data-sort-value="9" | 9 || 120 || New quadratic growth records || [[dani]], [[Luka Okanishi]], and [[Rocknlol]] ||
|- class="expand-child"
| colspan="5" | The smallest known [[quadratic growth]] patterns in terms of population, number of gliders, and bounding box — [[20-cell quadratic growth]], 6G quadratic growth, and 23×13 quadratic growth.
|-
| data-sort-value="11" | 11 || 116 || 74P34 || [[Mitchell Riley]] || [https://conwaylife.com/forums/viewtopic.php?p=147943#p147943]
|- class="expand-child"
| colspan="5" | The first known [[non-trivial]] oscillator with period 34.
|-
| data-sort-value="12" | 12 || 110 || New gun periods || [[David Raucci]], [[iNoMed]], [[Nico Brown]], [[Mitchell Riley]], [[goldenratio]], [[Luke Kiernan]], [[Gustone]] and [[cvojan]] || [https://conwaylife.com/forums/viewtopic.php?p=156004#p156004]
|- class="expand-child"
| colspan="5" | [[Gun]]s of five previously unsolved periods: 25, 27, 34, 37, and 43.
|-
| data-sort-value="13" | 13 || 107 || New stable conduits and converters || [[Mitchell Riley]], [[Simon Ekström]], [[Evin]], [[Entity Valkyrie]], [[Tanner Jacobi]], and [[qqd]] || [https://conwaylife.com/forums/viewtopic.php?p=162089#p162089]
|- class="expand-child"
| colspan="5" | Several new stable [[conduit]]s and [[converter]]s, including the [[Speed Tunnel]], HRx65R, a small stable 180° reflector (the "[[Jubjub reflector]]"), F149, Lx129, HL224H, RSE14T117, and NW-2T16.
|-
| data-sort-value="14" | 14 || 100 || New spaceship syntheses || [[Goldtiger997]], [[Mark Niemiec]], [[iNoMed]], [[Tanner Jacobi]], [[pipsqueek]], and [[Connor Steppie]] ||
|- class="expand-child"
| colspan="5" | Glider construction recipes were discovered for [[Orion 2]], [[33P4H1V1]], [[70P5H2V0]], [[58P8H4V0]], [[30P3H1V0]], [[29P3H1V0]], [[Brain]], [[66P5H2V0]], and [[37P4H1V1]], as well as a method for adding a component to existing [[c/3]] spaceships.
|-
| data-sort-value="15" | 15 || 99 || [[Quartermax]] || [[Keith Amling]], [[Hartmut Holzwart]], and [[Jason Summers]] || [https://conwaylife.com/forums/viewtopic.php?p=144986#p144986]
|- class="expand-child"
| colspan="5" | A long sought-after pattern that fills one quarter of the Life plane with the [[zebra stripes]] agar .
|-
| data-sort-value="16" | 16 || 98 || Soup search discoveries from distributed computing projects || [[Darren Li]] / [[Charity Engine]] and [[Open Science Grid]] || [https://conwaylife.com/wiki/Charity_Engine]
|- class="expand-child"
| colspan="5" | Thanks to the efforts of Darren Li, in 2022 [[Catagolue]] started receiving a much larger number of distributed-computing search results, especially for symmetric soups. This contributed to a large number of new discoveries; see the [[Charity Engine]] and [[Open Science Grid]] articles for examples.
|-
| data-sort-value="17" | 17 || 97 || Nico Brown's strictly volatile oscillators || [[Nico Brown]] || [https://conwaylife.com/forums/viewtopic.php?p=154361#p154361]
|- class="expand-child"
| colspan="5" | Nico Brown created a script that can create huge strictly volatile oscillators of any period 943+ except 944.
|-
| data-sort-value="18" | 18 || 93 || Smaller [[Period-24 glider gun|p24 glider gun]] || [[cvojan]], [[vivi]], and [[James Pascua]] || [https://conwaylife.com/forums/viewtopic.php?p=151697#p151697]
|- class="expand-child"
| colspan="5" | A new second-smallest [[glider gun]] after the [[Gosper glider gun]], fitting in a 20 × 20 bounding box.
|-
| data-sort-value="18" | 18 || 93 || New honeyfarm catalysts || [[Mitchell Riley]] and [[Luke Kiernan]] || [https://conwaylife.com/forums/viewtopic.php?p=163001#p163001]
|- class="expand-child"
| colspan="5" | Catalysts which perform new perturbations on [[honey farms]]. In particular the [[chucklebait]], which has found considerable use in [[honey farm hassler]]s of various periods.
|-
| data-sort-value="20" | 20 || 91 || [[232P7H3V0]] || [[Keith Amling]] || [https://conwaylife.com/wiki/232P7H3V0]
|- class="expand-child"
| colspan="5" | A new record for the smallest 3c/7 spaceship.
|-
| data-sort-value="21" | 21 || 90 || Completion of the [https://conwaylife.com/forums/viewtopic.php?p=153564#p153564 21-bit strict still life synthesis project] and the [https://conwaylife.com/forums/viewtopic.php?p=153274#p153274 20-bit pseudo still life synthesis project] || [[Alex Greason]], [[May13]], [[wwei23]], [[iNoMed]], [[Daniel Vargas]], [[Jeremy Tan]], [[Adam P. Goucher]], [[Carson Cheng]], [[Goldtiger997]], and [[Tanner Jacobi]] ||
|- class="expand-child"
| colspan="5" | Completion of the 21-bit strict still life synthesis project and the 20-bit pseudo still life synthesis project: Glider syntheses for all 21-bit strict still lifes and all 20-bit pseudo still lifes.
|-
| data-sort-value="22" | 22 || 88 || New [[greyship]]s || [[Hartmut Holzwart]] and [[Keith Amling]] || [https://conwaylife.com/forums/viewtopic.php?p=157297#p157297]
|- class="expand-child"
| colspan="5" | A variety of new greyships, many of which were found with Keith Amling’s new search program, [[LLSSS]].
|-
| data-sort-value="22" | 22 || 88 || p8 "functionally stable" glider reflector || [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=148209#p148209]
|- class="expand-child"
| colspan="5" | A period-8 180° glider [[reflector]] that works in every phase and hence can be used as if it were stable.
|-
| data-sort-value="24" | 24 || 85 || [[Strictly volatile p86]] R-pentomino hassler || [[Nico Brown]] and [[iNoMed]] || [https://conwaylife.com/forums/viewtopic.php?p=151276#p151276]
|- class="expand-child"
| colspan="5" | The discovery of this oscillator added 86 to a fairly short list, making it the fourteenth period where a strictly volatile oscillator is known that doesn't make use of self-constructing circuitry.
|-
| data-sort-value="24" | 24 || 85 || Five new p23 engines || [[Nico Brown]], [[James Pascua]], and [[Mitchell Riley]] || [https://conwaylife.com/forums/viewtopic.php?p=162150#p162150]
|- class="expand-child"
| colspan="5" | At the end of 2021, only one period-23 oscillator was known, excluding variants: David Hilbert. As of the end of 2022, there are six.
|-
| data-sort-value="26" | 26 || 82 || [[Taco]] || [[Frank Everdij]] || [https://conwaylife.com/forums/viewtopic.php?p=154464#p154464]
|- class="expand-child"
| colspan="5" | The third known [[elementary]] c/7 orthogonal spaceship.
|-
| data-sort-value="27" | 27 || 75 || Record lifespan puffer-based methuselahs || [[yaochen2]], [[dani]], and [[gravity]] || [https://conwaylife.com/forums/viewtopic.php?p=162979#p162979]
|- class="expand-child"
| colspan="5" | This series of patterns with relatively small bounding boxes and initial populations set several new records for [[methuselah]] longevity. Ordinarily patterns that include [[switch engine]] outputs will produce unbounded linear growth and are not counted in the "methuselah" category, but these examples generate a lucky retrograde glider that shuts down the receding switch engines after thousands or millions of [[generation]]s.
|-
| data-sort-value="28" | 28 || 73 || Small Max predcessors || [[iNoMed]] and [[rocknlol]] || [https://conwaylife.com/forums/viewtopic.php?p=155419#p155419]
|- class="expand-child"
| colspan="5" | After an intermediate 127-cell, 27 × 23 new record set by iNoMed, Rocknlol found two different record predecessors of a [[Max]] spacefiller variant by population and bounding box of 112 [[cell]]s and 21 × 21, respectively.
|-
| data-sort-value="29" | 29 || 69 || New reflector periods || [[vivi]], [[iNoMed]], [[Matthias Merzenich]], [[David Raucci]], [[Mitchell Riley]], [[MAP bot]], [[Nico Brown]], [[Tanner Jacobi]], and [[Noam Elkies]] || [https://conwaylife.com/forums/viewtopic.php?p=155493#p155493]
|- class="expand-child"
| colspan="5" | 90° reflectors for the previously unsolved periods of 23, 34, and 38.
|-
| data-sort-value="29" | 29 || 69 || Component for adding a "crotchet" to a c/3 spaceship || [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=154625#p154625]
|- class="expand-child"
| colspan="5" | This is a new synthesis component that can repeatably extend a "waltz" section of [[c/3 orthogonal]] spaceship, allowing for the first known infinite series of synthesizable c/3 spaceships.
|-
| data-sort-value="31" | 31 || 68 || New c/2 patterns from soup searches || [[mystical]], [[Charity Engine]], and [[wwei23]] ||
|- class="expand-child"
| colspan="5" | Spaceships, puffers, and a [[rake]] found from 'unnatural' soup searches. The ship [[58P8H4V0]] and a [[p28 block puffer]] were found in symmetric soups; the ship [[35P12H6V0]], the p112 puffer, and p12 rake were found in soups with the leading edge of the spaceships already present.
|-
| data-sort-value="32" | 32 || 56 || Gliderless Gosper glider gun breeder || [[Wojciech Kęsy]] || [https://conwaylife.com/forums/viewtopic.php?p=143050#p143050]
|- class="expand-child"
| colspan="5" | A p48 [[puffer]] for Gosper glider guns that produces its output in a very unconventional way, with no glider collisions.

|}
'''(Work in progress: copyediting)'''

===2021===
[https://conwaylife.com/forums/viewtopic.php?p=138613#p138613 Entries] • [https://conwaylife.com/forums/viewtopic.php?p=142893#p142893 Voting] • [https://conwaylife.com/forums/viewtopic.php?p=143872#p143872 Results]

In the {{year|2021}} competition, users were able to vote on as many patterns as they wish, awarding up to three stars to each one. [[MathAndCode]], [[Dave Greene]], and [[Kalan Warusa]] were each involved in organizing different parts of this year's competition.

(Note: A collection of links to many of these discoveries can be found in [https://conwaylife.com/forums/viewtopic.php?p=139123#p139123 this post] in the nominations thread.)

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Stars
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| 1 || 85 || [[Self-synthesizing oblique loopship]] || [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=134389#p134389]
|- class="expand-child"
| colspan="5" | The first SMOG (spaceship made of gliders) in Conway's Life. Arguably the first [[SMOS]] (spaceship made of spaceships) of any kind that can be run by [[Golly]], since [[0E0P]]-based SMOSes are much too large to simulate in practice.
|-
| 2 || 75 || [[Reflectorless rotating oscillator]] || [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=135135#p135135]
|- class="expand-child"
| colspan="5" | The first example of an [[RRO]] in Conway's Life that can easily be simulated through multiple cycles -- max loopability 11.
|-
| data-sort-value="3" | =3 || 68 || [[Traffic stop]] catalyst || [[cvojan]] || [https://conwaylife.com/forums/viewtopic.php?p=138895#p138895]
|- class="expand-child"
| colspan="5" | An extremely versatile p2 catalyst.
|-
| data-sort-value="3" | =3 || 68 || [[DOGun SaGaQR]] || [[Pavel Grankovskiy]] || [https://conwaylife.com/forums/viewtopic.php?p=138191#p138191]
|- class="expand-child"
| colspan="5" | A "shape-shifting" self-constructing pattern that can be trivially altered by one-tick adjustments to one key glider to make a predecessor of empty space ("D"=Diehard), a p100663296 oscillator ("O"=Oscillator),a 4-barrelled glider gun ("Gun"), an orthogonal c/24 spaceship ("S"=Spaceship), a single glider ("G"=Glider), or a quadratic-growth replicator("QR"=Quadratic Replicator).
|-
| data-sort-value="5" | =5 || 65 || New spaceship syntheses || [[goldenratio]], [[bubblegum]], [[Mark Niemiec]], [[iNoMed]], [[Goldtiger997]], and [[Martin Grant]] || [https://conwaylife.com/forums/viewtopic.php?p=120269#p120269] [https://conwaylife.com/forums/viewtopic.php?p=124810#p124810] [https://conwaylife.com/forums/viewtopic.php?p=128012#p128012] [https://conwaylife.com/forums/viewtopic.php?p=132334#p132334] [https://conwaylife.com/forums/viewtopic.php?p=132872#p132872] [https://conwaylife.com/forums/viewtopic.php?p=141536#p141536]
|- class="expand-child"
| colspan="5" | Several complex recipes for previously unsynthesizable spaceships, including [[greyship]]s of any desired size (the first being [[Canada Grey]]), as well as [[edge-repair spaceship 1]]
|-
| data-sort-value="5" | =5 || 65 || New gun engines || [[David Raucci]], [[Matthias Merzenich]], [[Luka Okanishi]], [[Tanner Jacobi]], [[Martin Grant]], [[Entity Valkyrie]], [[Adam P. Goucher]], [[iNoMed]], [[Louis-François Handfield]], [[Daniel Vargas]], [[praosylen]], [[Jiahao Yu]], [[James Pascua]], [[wwei23]], [[AforAmpere]], [[EvinZL]], and [[FWKnightship]] || Too many to list; a compilation (without forum links) can be found at [https://conwaylife.com/forums/viewtopic.php?p=142110#p142110]
|- class="expand-child"
| colspan="5" | Many new periodic engines that allow for the extraction of output gliders.
|-
| 7 || 64 || New [[(2,1)c/6]] technology || [[Dylan Chen]], [[Adam P. Goucher]], [[May13]], [[wwei23]], [[cvojan]], [[Dave Greene]], [[Louis-François Handfield]], [[Peter Naszvadi]], and [[Daniel Vargas]] || Too many to list; a compilation can be found at [https://conwaylife.com/forums/viewtopic.php?p=142372#p142372], while links to each individual discovery can be found at [https://conwaylife.com/forums/viewtopic.php?p=139123#p139123]
|- class="expand-child"
| colspan="5" | The second known elementary [[knightship]] and associated period-12N puffers, rakes, and new spaceship connection types
|-
| 8 || 62 || New scalable programmable computer || [[Nicolas Loizeau]] || [https://conwaylife.com/forums/viewtopic.php?p=136536#p136536]
|- class="expand-child"
| colspan="5" | New features and improvements include 90 pre-computed patterns, variable size range from 8 to 32, new instructions to handle arrays, variables usable as memory addresses, shift and rotate instructions, 32x32 pixels display, and circuitry optimization with [[Snark]] reflectors.
|-
| 9 || 57 || New high-period oscillators || [[David Raucci]], [[Entity Valkyrie]], [[James Pascua]], [[Matthias Merzenich]], [[wwei23]], [[praosylen]], [[Daniel Vargas]], [[iNoMed]], [[AforAmpere]], [[EvinZL]], [[Martin Grant]], and [[FWKnightship]] || Too many to list; a compilation (without forum links) can be found in [[User:Entity Valkyrie 2/2021 oscillator stamp|Entity Valkyrie's userspace]]
|- class="expand-child"
| colspan="5" | Many new oscillators with periods greater than 12 found primarily with Raucci's impressively simple and effective search script for oscillator engine candidates.
|-
| 10 || 56 || [[hotcrystal0 mechanism]] || [[hotcrystal0]], [[wwei23]], [[Entity Valkyrie]], [[praosylen]], [[iNoMed]], and [[May13]] || [https://conwaylife.com/forums/viewtopic.php?p=141587#p141587]
|- class="expand-child"
| colspan="5" | A new glider duplication mechanism capable, among other things, of reducing the size of a significant number of lower-period glider guns.
|-
| data-sort-value="11" | =11 || 52 || [[QuickSilver Demonoid]] || [[googolplex]] and [[Pavel Grankovskiy]] || [https://conwaylife.com/forums/viewtopic.php?p=138965#p138965]
|- class="expand-child"
| colspan="5" | A "[[steampunk]]" Demonoid using retro technology available in the 1990s, mainly [[Silver reflector]]s, but modern single-channel construction recipes and techniques.
|-
| data-sort-value="11" | =11 || 52 || new [[3c/7 orthogonal|3c/7]] technology || [[Dylan Chen]], [[Goldtiger997]], [[Matthias Merzenich]], [[iNoMed]], [[bubblegum]], [[Dave Greene]], [[AforAmpere]], [[wwei23]], and [[May13]] || Too many to list; a compilation (without forum links) can be found at [https://conwaylife.com/forums/viewtopic.php?p=141841#p141841]
|- class="expand-child"
| colspan="5" | A significant expansion of known 3c/7 technology including the first 3c/7 rakes, many new spaceships of various periods, and several new engine-based puffers.
|-
| 13 || 51 || New SKOPs || [[David Raucci]], [[praosylen]], [[iNoMed]], [[83bismuth38]], [[cvojan]], and [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=142359#p142359] [https://conwaylife.com/forums/viewtopic.php?p=133286#p133286] [https://conwaylife.com/forums/viewtopic.php?p=136555#p136555] [https://conwaylife.com/forums/viewtopic.php?p=132816#p132816] [https://conwaylife.com/forums/viewtopic.php?p=128061#p128061] [https://conwaylife.com/forums/viewtopic.php?p=133504#p133504] [https://conwaylife.com/forums/viewtopic.php?p=133518#p133518] [https://conwaylife.com/forums/viewtopic.php?p=135248#p135248] [https://conwaylife.com/forums/viewtopic.php?p=132959#p132959]
|- class="expand-child"
| colspan="5" | New Smallest Known Oscillators of various Periods. The term "SKOP" is from [[Jeremy Tan]]'s "Skopje" collection of smallest known oscillators. These include a new [[p25 pre-pulsar shuttle]], a [[p32 honey farm hassler]], [[66P62]], [[Raucci's p74]], a [[p76 pi-heptomino hassler]], a [[p96 honey farm hassler]], a [[p128 wing shuttle]], and a [[p196 pi-heptomino hassler]].
|-
| data-sort-value="14" | =14 || 46 || Twenty-bit still life syntheses || [[Dave Greene]], [[bubblegum]], [[Alex Greason]], [[Tanner Jacobi]], [[Jeremy Tan]], [[Goldtiger997]], [[Entity Valkyrie]], [[GUYTU6J]], [[Martin Grant]], [[goldenratio]], [[ENORMOUS_NAME]], [[Matthias Merzenich]], [[Daniel Vargas]], and [[iNoMed]] || [https://conwaylife.com/forums/viewtopic.php?p=125259#p125259]
|- class="expand-child"
| colspan="5" | [[Glider synthesis|Glider syntheses]] for all twenty-cell still lifes
|-
| data-sort-value="14" | =14 || 46 || Ash-clearing mechanism || [[Andrew J. Wade]] || [https://conwaylife.com/forums/viewtopic.php?p=136948#p136948]
|- class="expand-child"
| colspan="5" | Demonstration patterns and scripts showing for the first time a plausible mechanism for a "space-clearing" self-replicator with better than 50% odds of being able to clear out a replicator-sized area of settled random ash.
|-
| 16 || 44 || [[Strictly volatile p4]] oscillator || [[Dongook Lee]] || [https://conwaylife.com/forums/viewtopic.php?p=137807#p137807]
|- class="expand-child"
| colspan="5" | The first known period-4 oscillator with a [[strict volatility]] of 1 (no cells oscillating at any subperiod, in this case periods 1 or 2).
|-
| data-sort-value="17" | =17 || 42 || New [[c/6 orthogonal]] technology || [[FWKnightship]], [[Keith Amling]], [[May13]], and [[iNoMed]] || [https://conwaylife.com/forums/viewtopic.php?p=141785#p141785] [https://conwaylife.com/forums/viewtopic.php?p=133911#p133911] [https://conwaylife.com/forums/viewtopic.php?p=137540#p137540] [https://conwaylife.com/forums/viewtopic.php?p=137564#p137564] [https://conwaylife.com/forums/viewtopic.php?p=137653#p137653] [https://conwaylife.com/forums/viewtopic.php?p=137845#p137845] [https://conwaylife.com/forums/viewtopic.php?p=138128#p138128] [https://conwaylife.com/forums/viewtopic.php?p=137751#p137751] [https://conwaylife.com/forums/viewtopic.php?p=138498#p138498]
|- class="expand-child"
| colspan="5" | The first c/6 orthogonal rakes, based on new debris-clearing spaceships.
|-
| data-sort-value="17" | =17 || 42 || Herschel merge circuit || [[Entity Valkyrie]] and [[Luka Okanishi]] || [https://conwaylife.com/forums/viewtopic.php?p=137605#p137605]
|- class="expand-child"
| colspan="5" | The first known elementary merge circuit with two direct Herschel inputs and one Herschel output.
|-
| 19 || 38 || 12-in-7 and 15-in-11 projects || [[iNoMed]], [[Tanner Jacobi]], [[BlinkerSpawn]], [[goldenratio]], [[Oscar Cunningham]], [[Goldtiger997]], [[May13]], [[Daniel Vargas]], and [[Martin Grant]] || Too many to list; a compilation (without forum links) can be found at [https://conwaylife.com/forums/viewtopic.php?p=141702#p141702]
|- class="expand-child"
| colspan="5" | [[Glider synthesis|Glider syntheses]] of all still lifes with twelve (or fewer) cells using at most seven gliders, and fifteen or fewer cells using at most eleven gliders
|-
| 20 || 37 || New [[c/6 diagonal]] spaceships || [[Frank Everdij]], [[Bullet51]], and [[wwei23]] || [https://conwaylife.com/forums/viewtopic.php?p=141567#p141567] [https://conwaylife.com/forums/viewtopic.php?p=130230#p130230] [https://conwaylife.com/forums/viewtopic.php?p=130622#p130622] [https://conwaylife.com/forums/viewtopic.php?p=133347#p133347]
|- class="expand-child"
| colspan="5" | The number of known c/6 diagonal spaceships increased considerably this year, including some with new tailsparks and sidesparks capable of supporting a variety of [[tagalong]]s and [[pushalong]]s.
|-
| data-sort-value="21" | =21 || 34 || Fast [[component]]s || [[Daniel Vargas]], [[iNoMed]], [[Tanner Jacobi]], [[wwei23]], and [[BlinkerSpawn]] || [https://conwaylife.com/forums/viewtopic.php?p=123124#p123124]
|- class="expand-child"
| colspan="5" | Timing-dependent ways to stabilize reactions that almost make still lifes or alter still life-creating reactions or slow components before they settle in order to modify the final result
|-
| data-sort-value="21" | =21 || 34 || New record [[methuselah]]s || [[Dylan Chen]], [[Rocknlol]], [[Adam P. Goucher]], [[Daniel Vargas]], and [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=118690#p118690] [https://conwaylife.com/forums/viewtopic.php?p=119406#p119406] [https://conwaylife.com/forums/viewtopic.php?p=136939#p136939]
|- class="expand-child"
| colspan="5" | New methuselahs with record lifespans, including [[50093M]] and [[52513M]], based on soups discovered with [[apgsearch]].
|-
| data-sort-value="21" | =21 || 34 || Chicken wire grayships || [[Hartmut Holzwart]] and [[Arie Paap]] || Too many to list; a compilation (without forum links) can be found at [https://conwaylife.com/forums/viewtopic.php?p=141693#p141693]
|- class="expand-child"
| colspan="5" | Many new components for constructing chicken wire [[grayship]]s including slope-0 back ends for almost all wire lengths.
|-
| data-sort-value="24" | =24 || 32 || New [[Period-7 sparkers#Domino sparkers|p7 domino sparkers]] || [[wwei23]], [[BlinkerSpawn]], [[iNoMed]], [[James Pascua]], [[cvojan]], and [[Dongook Lee]] || [[754P7]]
|- class="expand-child"
| colspan="5" | Oscillators that provide a domino spark every seven generations, which can be used to support other reactions. Notable discoveries in 2021 include [[62P7]] and [[678P7]].
|-
| data-sort-value="24" | =24 || 32 || New [[c/10 orthogonal|c/10]] technology || [[Christoph Reinthaler]], [[otismo]], [[Goldtiger997]], [[Louis-François Handfield]], and [[Dave Greene]] || Too many to list; a compilation can be found at [https://conwaylife.com/forums/viewtopic.php?p=142340#p142340] while the original forum thread can be found at [https://conwaylife.com/forums/viewtopic.php?p=118271#p118271] (starting with the first post of 2021)
|- class="expand-child"
| colspan="5" | New c/10 orthogonal glider perturbation reactions, rake periods, and complex patterns.
|-
| 26 || 31 || Much smaller glider to [[weekender]]/[[doo-dah]] converter || [[Dave Greene]] and [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=137616#p137616]
|- class="expand-child"
| colspan="5" | 2021's enormously reduced weekender recipe allowed for a glider-to-weekender converter to fit into a quarter of its previous area, even including an additional mechanism to build/not build a doo-dah tagalong by moving an input glider.
|-
| 27 || 28 || p18 glider reflectors || [[David Raucci]], [[Matthias Merzenich]], and [[EvinZL]] || [https://conwaylife.com/forums/viewtopic.php?p=135235#p135235]
|- class="expand-child"
| colspan="5" | Period-18 glider reflectors including the first 90-degree reflector capable of reflecting a period-18 glider stream.
|-
| 28 || 24 || [[2c/5 orthogonal|2c/5]] ant waveguide || [[Matthias Merzenich]], [[Adam P. Goucher]], and [[Nicolay Beluchenko]] || [https://conwaylife.com/forums/viewtopic.php?p=141475#p141475]
|- class="expand-child"
| colspan="5" | A previously unknown type of spaceship connection, where an [[ants]] wick is escorted by a 2c/5 orthogonal antstretcher and anteater, making an adjustable-size spaceship (and not a growing spaceship)
|-
| data-sort-value="29" | =29 || 22 || p33 statorless 90-degree glider reflector || [[FractalFusion]] || [https://conwaylife.com/forums/viewtopic.php?p=138634#p138634]
|- class="expand-child"
| colspan="5" | Reaction involving many copies of [[Jason's p33]] allows for [[statorless]] oscillators of all periods that are multiples of 33.
|-
| data-sort-value="29" | =29 || 22 || [[p3 pipsquirter]]s || [[James Pascua]], [[83bismuth38]], [[cvojan]], [[Dongook Lee]], [[Mark Niemiec]], [[Jiahao Yu]], and [[iNoMed]] || [https://conwaylife.com/forums/viewtopic.php?p=142074#p142074] [https://conwaylife.com/forums/viewtopic.php?p=134824#p134824] [https://conwaylife.com/forums/viewtopic.php?p=136874#p136874] [https://conwaylife.com/forums/viewtopic.php?p=136890#p136890] [https://conwaylife.com/forums/viewtopic.php?p=136905#p136905]
|- class="expand-child"
| colspan="5" | Several new variants of oscillators with an isolated domino spark in the same orientation as known higher-period pipsquirters. These sparks can be used to support other oscillators such as the carnival shuttle (though they're far from the first known supports for that particular case)
|-
| 31 || 21 || [[T-nosed p7]] || [[Martin Grant]] || [https://conwaylife.com/forums/viewtopic.php?p=134269#p134269]
|- class="expand-child"
| colspan="5" | New p7 sparker completed based on a suggestion by [[Connor Steppie]].
|-
| 32 || 19 || [[p11 bouncer]] || [[Martin Grant]] and [[David Raucci]] || [https://conwaylife.com/forums/viewtopic.php?p=138670#p138670]
|- class="expand-child"
| colspan="5" | A previously unknown period for the [[bouncer]] mechanism (a [[p11 bumper]] was known, though very little used).
|}

===2020===
[https://conwaylife.com/forums/viewtopic.php?p=117558#p117558 Entries] • [https://conwaylife.com/forums/viewtopic.php?p=123463#p123463 Voting] • [https://conwaylife.com/forums/viewtopic.php?p=126089#p126089 Results]

The following patterns were voted on for the {{year|2020}} competition. Users were able to vote on as many patterns as they wished, awarding up to three stars to each one. [[MathAndCode]] organized the competition.

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Stars
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| data-sort-value="1" | =1 || 76 || [[Bandersnatch]] || [[Martin Grant]] and [[Entity Valkyrie]] || [https://conwaylife.com/forums/viewtopic.php?p=98357#p98357]
|- class="expand-child"
| colspan="5" | A [[color-changing]] glider-to-glider conduit, which can be used to solve glider color mismatches.
|-
| data-sort-value="1" | =1 || 76 || [[Speed Demonoid]] || [[Pavel Grankovskiy]], [[Dave Greene]], [[Tanner Jacobi]], and [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=104423#p104423]
|- class="expand-child"
| colspan="5" | A self-constructing diagonal spaceship with speed limit c/4 due to using a crab [[wickstretcher]].
|-
| 3 || 69 || Spaceship [[glider syntheses]] || [[Goldtiger997]], [[Tanner Jacobi]], [[Martin Grant]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=91947#p91947] [https://conwaylife.com/forums/viewtopic.php?p=92323#p92323] [https://conwaylife.com/forums/viewtopic.php?p=93110#p93110] [https://conwaylife.com/forums/viewtopic.php?p=93167#p93167] [https://conwaylife.com/forums/viewtopic.php?p=93825#p93825] [https://conwaylife.com/forums/viewtopic.php?p=93897#p93897] [https://conwaylife.com/forums/viewtopic.php?p=98477#p98477] [https://conwaylife.com/forums/viewtopic.php?p=100747#p100747] [https://conwaylife.com/forums/viewtopic.php?p=101622#p101622] [https://conwaylife.com/forums/viewtopic.php?p=103142#p103142] [https://conwaylife.com/forums/viewtopic.php?p=104453#p104453] [https://conwaylife.com/forums/viewtopic.php?p=114209#p114209]
|- class="expand-child"
| colspan="5" | Glider syntheses for [[56P6H1V0]], [[58P5H1V1]], [[turtle]], [[31P8H4V0]], [[70P2H1V0.1]], [[55P9H3V0]], and [[44P5H2V0]], many of which were the first of their unsymplified speed to be synthesized.
|-
| data-sort-value="4" | =4 || 68 || Smaller [[3c/7]] spaceships || [[Dylan Chen]] || [https://conwaylife.com/forums/viewtopic.php?p=117159#p117159] [https://conwaylife.com/forums/viewtopic.php?p=117548#p117548]
|- class="expand-child"
| colspan="5" | [[Anura]] and [[Soba]], the second and third known elementary 3c/7 spaceships, both of which are smaller than the first known 3c/7 spaceship, [[spaghetti monster]].
|-
| data-sort-value="4" | =4 || 68 || [[Rob's p16]] || [[Rob Liston]] || [https://conwaylife.com/forums/viewtopic.php?p=89261#p89261]
|- class="expand-child"
| colspan="5" | A useful sparker, as well as the smallest-known and first [[strictly volatile]] oscillator of its period, found when it occurred in the ash of an asymmetric Catagolue soup.
|-
| 6 || 65 || [[Period-28 glider gun]] || [[Matthias Merzenich]] and [[Paul Callahan]] || [https://conwaylife.com/forums/viewtopic.php?p=115869#p115869] [https://conwaylife.com/forums/viewtopic.php?p=115928#p115928]
|- class="expand-child"
| colspan="5" | The first true period-28 gun.
|-
| 7 || 64 || [[Silverfish]] || [[Chris Cain]], [[Dave Greene]], [[Adam P. Goucher]], and [[Nathaniel Johnston]] || [https://conwaylife.com/forums/viewtopic.php?p=96462#p96462]
|- class="expand-child"
| colspan="5" | A new smallest spaceship to use the 31c/240 Herschel climber.
|-
| 8 || 61 || Cheaper fixed-cost [[universal construction]] || [[Chris Cain]], [[Adam P. Goucher]] [[Daniel Vargas]], and [[MathAndCode]] || [https://conwaylife.com/forums/viewtopic.php?p=94346#p94346] [https://conwaylife.com/forums/viewtopic.php?p=100871#p100871] [https://conwaylife.com/forums/viewtopic.php?p=104484#p104484]
|- class="expand-child"
| colspan="5" | Reductions in the cost of [[reverse caber-tosser]]-based universal construction by figuring out how to split a target block with gliders instead of needing to use a block-laying switch engine, removing the need for a Sakapuffer, and reducing the number of glider-producing switch enginges required in the circuitry.
|-
| 9 || 58 || 19-bit still life syntheses || [[Jeremy Tan]], [[Dave Greene]], [[Tanner Jacobi]], [[Goldtiger997]], [[Martin Grant]], [[Alex Greason]], [[BlinkerSpawn]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=89061#p89061]
|- class="expand-child"
| colspan="5" | Glider syntheses for all 19-bit still lifes.
|-
| data-sort-value="10" | =10 || 56 || New [[2c/7]] technology || [[John Winston Garth]], [[Andrew J. Wade]] || [https://conwaylife.com/forums/viewtopic.php?p=92001#p92001] [https://conwaylife.com/forums/viewtopic.php?p=114481#p114481]
|- class="expand-child"
| colspan="5" | Two new 2c/7 spaceships, [[186P7H2V0]] and [[doo-dah]] used to help make puffers and rakes.
|-
| data-sort-value="10" | =10 || 56 || Natural [[loafer]]s || [[John Goodman]], [[Rob Liston]], [[Adam P. Goucher]] || [https://conwaylife.com/forums/viewtopic.php?p=93011#p93011] [https://conwaylife.com/forums/viewtopic.php?p=98270#p98270] [https://conwaylife.com/forums/viewtopic.php?p=102387#p102387] [https://conwaylife.com/forums/viewtopic.php?p=116445#p116445]
|- class="expand-child"
| colspan="5" | Catagolue soups in the C1 and G1 symmetries that produce the twenty-cell loafer, making it the first spaceship not at the maximum speed for its direction to be found in a random asymmetric soup in B3/S23.
|-
| 12 || 55 || Stable [[barge]] crosser || [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=112239#p112239]
|- class="expand-child"
| colspan="5" | A way to transmit a glider signal across an infinitely long barge without permanently damaging it.
|-
| 13 || 50 || New [[grayship]] technology || [[Keith Amling]], [[Hartmut Holzwart]], and [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=117591#p117591]
|- class="expand-child"
| colspan="5" | A large collection of new grayship components of varying speeds.
|-
| 14 || 46 || [[Beehive push catalyst]] || [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=116491#p116491]
|- class="expand-child"
| colspan="5" | A [[stable]] catalyst that allows the beehive push reaction, where a beehive affects an active region while being displaced by one cell orthogonally, to be used repeatedly in situations where there is not another synchronized mechanism to push it back, such as in conduits.
|-
| 15 || 45 || [[49768M|New longest-lasting 16x16 methuselah]] || [[Rob Liston]] and [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=95336#p95336]
|- class="expand-child"
| colspan="5" | An asymmetric 16x16 soup found with Catagolue that takes longer to stabilize than any previous asymmetric non-infinite-growth 16x16 soup, and a related 16x16 pattern that takes one generation longer to form generation five of said random soup.
|-
| 16 || 44 || New [[c/5 diagonal]] spaceships || [[AforAmpere]], [[Sarp]], [[praosylen]], [[John Winston Garth]], and [[Dylan Chen]] || [https://conwaylife.com/forums/viewtopic.php?p=117609#p117609] [https://conwaylife.com/forums/viewtopic.php?p=92434#p92434] [https://conwaylife.com/forums/viewtopic.php?p=94109#p94109] [https://conwaylife.com/forums/viewtopic.php?p=94294#p94294] [https://conwaylife.com/forums/viewtopic.php?p=94332#p94332] [https://conwaylife.com/forums/viewtopic.php?p=95431#p95431] [https://conwaylife.com/forums/viewtopic.php?p=95843#p95843] [https://conwaylife.com/forums/viewtopic.php?p=96217#p96217] [https://conwaylife.com/forums/viewtopic.php?p=96478#p96478] [https://conwaylife.com/forums/viewtopic.php?p=98297#p98297] [https://conwaylife.com/forums/viewtopic.php?p=114110#p114110]
|- class="expand-child"
| colspan="5" | Several new c/5 diagonal spaceships of varying shapes.
|-
| 17 || 43 || Small [[c/5 diagonal]] puffer || [[Peter Naszvadi]] || [https://conwaylife.com/forums/viewtopic.php?p=92484#p92484]
|- class="expand-child"
| colspan="5" | An elegant period-1540 c/5 diagonal puffer that uses only three copies of [[58P5H1V1]].
|-
| 18 || 42 || New small [[Cordership]]s || [[wwei23]] and [[Ian07]] || [https://conwaylife.com/forums/viewtopic.php?p=103715#p103715] [https://conwaylife.com/forums/viewtopic.php?p=103853#p103853] [https://conwaylife.com/forums/viewtopic.php?p=103997#p103997] [https://conwaylife.com/forums/viewtopic.php?p=104102#p104102] [https://conwaylife.com/forums/viewtopic.php?p=104197#p104197]
|- class="expand-child"
| colspan="5" | Several new three-engine and four-engine Corderships (including [[4-in-a-row Cordership|one with period 192]]) found using a custom apgsearch symmetry.
|-
| data-sort-value="19" | =19 || 41 || New [[agar]] crawler/agar bubble/[[skimmer]]/agar clearer technology || [[Arie Paap]], [[Keith Amling]], [[Hartmut Holzwart]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=94779#p94779] [https://conwaylife.com/forums/viewtopic.php?p=101259#p101259] [https://conwaylife.com/forums/viewtopic.php?p=104295#p104295]
|- class="expand-child"
| colspan="5" | Mechanisms to add, remove, travel along, or travel within agar.
|-
| data-sort-value="19" | =19 || 41 || [[c/5]] and [[c/6]] guns || [[Entity Valkyrie]], [[Goldtiger997]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=88186#p88186] [https://conwaylife.com/forums/viewtopic.php?p=97489#p97489] [https://conwaylife.com/forums/viewtopic.php?p=114939#p114939]
|- class="expand-child"
| colspan="5" | The first known guns for c/5 orthogonal, c/5 diagonal, and c/6 orthogonal spaceships.
|-
| data-sort-value="21" | =21 || 39 || New exotic spaceship eaters and spaceship-to-G converters || [[Jeremy Tan]], [[Luka Okanishi]], [[Dave Greene]], [[Adam P. Goucher]], [[Tanner Jacobi]], [[praosylen]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=99196#p99196] [https://conwaylife.com/forums/viewtopic.php?p=99438#p99438] [https://conwaylife.com/forums/viewtopic.php?p=99516#p99516] [https://conwaylife.com/forums/viewtopic.php?p=99527#p99527] [https://conwaylife.com/forums/viewtopic.php?p=100370#p100370] [https://conwaylife.com/forums/viewtopic.php?p=100403#p100403]
|- class="expand-child"
| colspan="5" | New mechanisms to eat spaceships or turn them into glider signals
|-
| data-sort-value="21" | =21 || 39 || Glider syntheses from Glider_stdin || [[testitemqlstudop]], [[Tanner Jacobi]], [[Arie Paap]], [[GUYTU6J]], [[goldenratio]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=87355#p87355] [https://conwaylife.com/forums/viewtopic.php?p=87709#p87709] [https://conwaylife.com/forums/viewtopic.php?p=88647#p88647] [https://conwaylife.com/forums/viewtopic.php?p=100655#p100655]
|- class="expand-child"
| colspan="5" | Glider syntheses based on a result from a custom Catagolue symmetry where gliders are fired at each other in a random configuration.
|-
| data-sort-value="21" | =21 || 39 || [[104P9|Period-9 heavyweight sparker]] and associated R shuttle || [[wwei23]], [[praosylen]], and [[David Raucci]] || [https://conwaylife.com/forums/viewtopic.php?p=115233#p115233]
|- class="expand-child"
| colspan="5" | Period-nine domino sparker that has two dot sparks displaced (2.5, 1) from the center of the domino spark, making it a heavyweight emulator, and has better clearance than the previous known period-nine domino sparker, allowing it and an eater 2 to form a periodic RFx9R conduit that can be attached to another copy of itself to form a shuttle
|-
| 24 || 38 || Stable [[L122]] || [[praosylen]] || [https://conwaylife.com/forums/viewtopic.php?p=100820#p100820]
|- class="expand-child"
| colspan="5" | A stable version of the L122 conduit, which previously only had periodic versions.
|-
| 25 || 35 || New [[c/10 orthogonal]] technology || [[Christoph Reinthaler]] || [https://conwaylife.com/forums/viewtopic.php?p=86970#p86970] [https://conwaylife.com/forums/viewtopic.php?p=115489#p115489]
|- class="expand-child"
| colspan="5" | Arrangements of copperheads and fireships that perform various tasks, such as firing a stream of loafers backwards.
|-
| data-sort-value="26" | =26 || 34 || New XWSS signal technology || [[Dave Greene]], [[Adam P. Goucher]], and [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=98622#p98622] [https://conwaylife.com/forums/viewtopic.php?p=99834#p99834]
|- class="expand-child"
| colspan="5" | Improved mechanisms for detecting XWSS signals.
|-
| data-sort-value="26" | =26 || 34 || Cordercolumn and extruder || [[wwei23]], [[Luka Okanishi]], and [[Ian07]] || [https://conwaylife.com/forums/viewtopic.php?p=104435#p104435] [https://conwaylife.com/forums/viewtopic.php?p=104815#p104815] [https://conwaylife.com/forums/viewtopic.php?p=104919#p104919]
|- class="expand-child"
| colspan="5" | Two ways to stabilize a switch engine with another switch engine behind it and an extruder that emits a line of switch engines using one of the methods.
|-
| data-sort-value="26" | =26 || 34 || New [[c/6 diagonal]] pushalong || [[praosylen]] || [https://conwaylife.com/forums/viewtopic.php?p=95237#p95237]
|- class="expand-child"
| colspan="5" | The first new piece of low-period c/6 diagonal technology in 9 years.
|-
| data-sort-value="26" | =26 || 34 || Better [[universal regulator]] || [[Louis-François Handfield]] || [https://conwaylife.com/forums/viewtopic.php?p=93912#p93912]
|- class="expand-child"
| colspan="5" | A device that can align a set of input glider signals with no period constraints to any output period greater than 73 that is smaller and faster than any previous universal regulator.
|-
| data-sort-value="26" | =26 || 34 || c/61 near-spaceship and [[slide gun]] support || [[Tanner Jacobi]] and [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=116260#p116260]
|- class="expand-child"
| colspan="5" | A reaction consisting of a pulsar interacting with two blocks that results in the same confirmation 61 generations later shifted by one cell orthogonally if supplied with two dot sparks or certain fishhook-type interactions, which can be provided with gliders from slide guns.
|-
| data-sort-value="31" | =31 || 33 || Record-setting [[diehard]]s || [[Rob Liston]], [[goldenratio]], and Moth-Wingthane || [https://conwaylife.com/forums/viewtopic.php?p=90882#p90882] [https://conwaylife.com/forums/viewtopic.php?p=116335#p116335]
|- class="expand-child"
| colspan="5" | Patterns found from soup searches searches that take longer to settle without leaving any ash than any previously known patterns fitting in a bounding box of the same size.
|-
| data-sort-value="31" | =31 || 33 || 4×N [[block]] agar construction || [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=96210#p96210]
|- class="expand-child"
| colspan="5" | A way to extend the pseudo still life consisting of a 4×3 rectangle of blocks to a 4×N rectangle for arbitrarily high N using gliders.
|-
| data-sort-value="31" | =31 || 33 || [[409P6H1V0|Width-12 c/6 orthogonal spaceship]] || [[Andrew J. Wade]] || [https://conwaylife.com/forums/viewtopic.php?p=91518#p91518]
|- class="expand-child"
| colspan="5" | The first width-12 asymmetric c/6 orthogonal spaceship, which has the minimum possible width for a asymmetric period-6 spaceship of this speed.
|-
| 34 || 32 || [[Loafer]] bitmap printer || [[otismo]] || [https://conwaylife.com/forums/viewtopic.php?p=107683#p107683] [https://conwaylife.com/forums/viewtopic.php?p=108412#p108412]
|- class="expand-child"
| colspan="5" | A collection of loafer guns that can be toggled by a glider memory tape to produce a message in loafer-pixels.
|-
| 35 || 30 || 34-bit still life enumeration || [[Nathaniel Johnston]] || [https://conwaylife.com/forums/viewtopic.php?p=87225#p87225]
|- class="expand-child"
| colspan="5" | An enumeration of all 34-bit still lifes and pseudo still lifes, which confirmed that the [[quad pseudo still life]] is the unique 34-bit pseudo still life requiring a decomposition into 4 or more pieces.
|-
| 36 || 27 || p5 drifter-like catalyst/lightweight volcano/periodic catalyst || [[wwei23]] and [[Dongook Lee]] || [https://conwaylife.com/forums/viewtopic.php?p=117492#p117492] [https://conwaylife.com/forums/viewtopic.php?p=117606#p117606]
|- class="expand-child"
| colspan="5" | An oscillator that periodically creates then kills via overpopulation a "[[block]] face", allowing it to be used to perturb regions in the same manner as several [[catalysts]] without permanently harming the oscillator.
|-
| 37 || 26 || New [[growing spaceship]]s || [[Matthias Merzenich]] and [[praosylen]] || [https://conwaylife.com/forums/viewtopic.php?p=114020#p114020] [https://conwaylife.com/forums/viewtopic.php?p=114280#p114280]
|- class="expand-child"
| colspan="5" | Patterns in which spaceships create a [[wick]] that is consumed at a slower speed than it is created at.
|-
| 38 || 25 || Period-10 glider shuttle || [[Martin Grant]] || [https://conwaylife.com/forums/viewtopic.php?p=110811#p110811]
|- class="expand-child"
| colspan="5" | The lowest known period for a glider [[shuttle]].
|-
| 39 || 23 || Extensible [[Lumps of muck|LoM]] hasslers || [[James Pascua]], [[wwei23]], and [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=117054#p117054] [https://conwaylife.com/forums/viewtopic.php?p=117098#p117098]
|- class="expand-child"
| colspan="5" | Extensible oscillators based on lumps of muck .
|}

===2019===
[https://conwaylife.com/forums/viewtopic.php?p=86701#p86701 Entries] • [https://conwaylife.com/forums/viewtopic.php?p=88378#p88378 Voting] • [https://conwaylife.com/forums/viewtopic.php?p=91252#p91252 Results]

The following patterns were voted on for the {{year|2019}} competition. Users were able to vote on as many patterns as they wished, awarding up to three stars to each one. [[testitemqlstudop]] organized the competition.

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Stars
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| 1 || 74 || [[David Hilbert]] || [[Luka Okanishi]], [[praosylen]] || [https://conwaylife.com/forums/viewtopic.php?p=85719#p85719]
|- class="expand-child"
| colspan="5" | The first {{period|23}} [[oscillator]] discovered.
|-
| 2 || 66 || [[Spider]] synthesis || [[Martin Grant]], [[Goldtiger997]], [[Tanner Jacobi]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=72705#p72705] [https://conwaylife.com/forums/viewtopic.php?p=86121#p86121] [https://conwaylife.com/forums/viewtopic.php?p=87949#p87949]
|- class="expand-child"
| colspan="5" | The first [[glider synthesis]] of a [[c/5 orthogonal]] [[spaceship]], and the largest [[elementary spaceship]] synthesis to date.
|-
| 3 || 53 || [[Scholar]] || [[Andrew J. Wade]] || [https://conwaylife.com/forums/viewtopic.php?p=86724#p86724]
|- class="expand-child"
| colspan="5" | The second elementary [[2c/7 orthogonal]] spaceship to be discovered, using a new search program named [https://gitlab.com/andrew-j-wade/life_slice_ship_search life_slice_ship_search].
|-
| data-sort-value="4" | =4 || 48 || [[46P4H1V0]] synthesis and [[gun]] || [[Tanner Jacobi]], [[Matthias Merzenich]], [[Martin Grant]], [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=69591#p69591] [https://conwaylife.com/forums/viewtopic.php?p=70272#p70272] [https://conwaylife.com/forums/viewtopic.php?p=84423#p84423]
|- class="expand-child"
| colspan="5" | The first synthesis and the first gun to produce a [[c/4 orthogonal]] spaceship.
|-
| data-sort-value="4" | =4 || 48 || Cheap [[still life]] syntheses || [[Tanner Jacobi]], [[Goldtiger997]], [[Jeremy Tan]], [[Adam P. Goucher]], [[Chris Cain]], [[2718281828]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=86078#p86078] [https://conwaylife.com/forums/viewtopic.php?p=85457#p85457] [https://conwaylife.com/forums/viewtopic.php?p=82560#p82560] [https://conwaylife.com/forums/viewtopic.php?p=83979#p83979]
|- class="expand-child"
| colspan="5" | Among other things, the construction of all 17-bit still lifes in at most 16 [[glider]]s (less than one glider per bit) and all 18-bit still lifes in at most 38 gliders.
|-
| data-sort-value="6" | =6 || 45 || [[Knightwave]] stablization || [[Matthias Merzenich]], [[Adam P. Goucher]] || [https://conwaylife.com/forums/viewtopic.php?p=68044#p68044]
|- class="expand-child"
| colspan="5" | The discovery that [[Sir_Robin#Tagalongs|Minstrel 2]] can be used to support both ends of the knightwave, allowing for extensible [[knightship]]s.
|-
| data-sort-value="6" | =6 || 45 || [[Remini]] || [[Michael Simkin]] || [https://conwaylife.com/forums/viewtopic.php?p=74984#p74984]
|- class="expand-child"
| colspan="5" | A [[universal constructor]]-based [[puffer]], made only with p30 technology theoretically available since the 1970s.
|-
| 8 || 41 || [[Dueling banjos]] and p24 gun || [[Apple Bottom]], [[Tanner Jacobi]], [[Matthias Merzenich]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=67718#p67718] [https://conwaylife.com/forums/viewtopic.php?p=67805#p67805] [https://conwaylife.com/forums/viewtopic.php?p=67883#p67883]
|- class="expand-child"
| colspan="5" | A new {{period|24}} oscillator and resulting compact p24 gun.
|-
| 9 || 39 || [[Slavic]] || [[Pavel Grankovskiy]] || [https://conwaylife.com/forums/viewtopic.php?p=86540#p86540]
|- class="expand-child"
| colspan="5" | The current smallest universal-constructor based [[quadratic growth]] pattern.
|-
| data-sort-value="10" | =10 || 37 || [[Wings]] synthesis and gun || [[Goldtiger997]], [[BlinkerSpawn]], [[Entity Valkyrie]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=84593#p84593] [https://conwaylife.com/forums/viewtopic.php?p=84785#p84785]
|-
| data-sort-value="10" | =10 || 37 || Stable glider-to-spaceship [[converter]]s || [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=76686#p76686] [https://conwaylife.com/forums/viewtopic.php?p=77029#p77029] [https://conwaylife.com/forums/viewtopic.php?p=86384#p86384]
|- class="expand-child"
| colspan="5" | Stable patterns that convert gliders into small synthesizable spaceships ([[crab]], [[25P3H1V0.2]], [[wings]]).
|-
| 12 || 36 || [[66P13]] || [[Bullet51]], [[praosylen]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=85245#p85245] [https://conwaylife.com/forums/viewtopic.php?p=85261#p85261] [https://conwaylife.com/forums/viewtopic.php?p=85862#p85862]
|- class="expand-child"
| colspan="5" | A sparky {{period|13|text=period-13}} oscillator which can support [[wick]]s, [[bumper]]s, and p26 oscillators.
|-
| 13 || 35 || [[p49 skewed pulsar hassler]] || [[Martin Grant]], [[Jason Summers]] || [https://conwaylife.com/forums/viewtopic.php?p=85900#p85900]
|- class="expand-child"
| colspan="5" | The first known p49 oscillator that is not a [[glider loop]].
|-
| data-sort-value="14" | =14 || 34 || [[Phoenix]] [[agar]]s || [[Alex Greason]], [[BlinkerSpawn]], [[Dongook Lee]], and [[Arie Paap]] || [https://conwaylife.com/forums/viewtopic.php?p=84877#p84877] [https://conwaylife.com/forums/viewtopic.php?p=84994#p84994] [https://conwaylife.com/forums/viewtopic.php?p=84928#p84928]
|- class="expand-child"
| colspan="5" | Oscillating patterns living on a period-2 phoenix background that emulate some bounded [https://en.wikipedia.org/wiki/Elementary_cellular_automaton Rule 18] patterns.
|-
| data-sort-value="14" | =14 || 34 || 60-line c/10 printer || [[GilGil]] || [https://conwaylife.com/forums/viewtopic.php?p=76571#p76571]
|- class="expand-child"
| colspan="5" | An easy-to-use [[c/10 orthogonal]] printer that can copy and print a picture 60 lines tall.
|-
| data-sort-value="16" | =16 || 33 || [[R49]] || [[Entity Valkyrie]], [[Luka Okanishi]] || [https://conwaylife.com/forums/viewtopic.php?p=83753#p83753]
|- class="expand-child"
| colspan="5" | A useful and compact pre-[[Herschel]] [[turner]]/advancer [[conduit]].
|-
| data-sort-value="16" | =16 || 33 || New gun designs || [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=75185#p75185] [https://conwaylife.com/forums/viewtopic.php?p=75374#p75374]
|- class="expand-child"
| colspan="5" | Clever new gun components that allow the reduction of a large number of glider guns in the [[Dieter and Peter's glider gun collection|small guns collection]].
|-
| data-sort-value="16" | =16 || 33 || Systematic survey of small patterns || [[Nick Gotts]] || [https://conwaylife.com/forums/viewtopic.php?p=65971#p65971] [https://conwaylife.com/forums/viewtopic.php?p=77105#p77105] [https://conwaylife.com/forums/viewtopic.php?p=85059#p85059]
|- class="expand-child"
| colspan="5" | A systematic survey of all patterns up to 9 cells, as well as a survey of all single-cluster 10-cell patterns resulting in the discovery of two record-breaking 10-celled methuselae, [[bunnies 10a]] and [[bunnies 10b]].
|-
| data-sort-value="19" | =19 || 32 || 99 Bottles of Beer on the Wall || [[Michael Simkin]] || [https://conwaylife.com/forums/viewtopic.php?p=85414#p85414]
|- class="expand-child"
| colspan="5" | A pattern that prints the song "99 Bottles of Beer on the Wall."
|-
| data-sort-value="19" | =19 || 32 || [[Spaghetti monster]] eater and [[Heisenburp]] || [[Martin Grant]], [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=84018#p84018] [https://conwaylife.com/forums/viewtopic.php?p=84081#p84081]
|- class="expand-child"
| colspan="5" | The first patterns capable of cleanly deleting and detecting a [[3c/7 orthogonal]] spaceship.
|-
| 21 || 29 || [[47575M]] || [[Adam P. Goucher]] || [https://conwaylife.com/forums/viewtopic.php?p=70221#p70221]
|- class="expand-child"
| colspan="5" | A record-breaking [[methuselah]] (excluding [[switch engine]]-based methuselahs) found with [[apgsearch]].
|-
| 22 || 27 || Mountain range patterns || [[Dean Hickerson]] || [https://conwaylife.com/forums/viewtopic.php?p=72684#p72684]
|- class="expand-child"
| colspan="5" | Various patterns experiencing irregular growth due to complex glider interactions in a similar vein to [[jagged lines]].
|-
| data-sort-value="23" | =23 || 26 || New mid-period [[sparker]]s || [[2718281828]], [[praosylen]], [[Martin Grant]], [[Dongook Lee]] || [https://conwaylife.com/forums/viewtopic.php?p=70587#p70587] [https://conwaylife.com/forums/viewtopic.php?p=70632#p70632] [https://conwaylife.com/forums/viewtopic.php?p=75715#p75715] [https://conwaylife.com/forums/viewtopic.php?p=76104#p76104] [https://conwaylife.com/forums/viewtopic.php?p=77040#p77040] [https://conwaylife.com/forums/viewtopic.php?p=84992#p84992] [https://conwaylife.com/forums/viewtopic.php?p=85532#p85532]
|-
| data-sort-value="23" | =23 || 26 || Stably supported [[cyclotron]] gun || [[Goldtiger997]], [[Paul Callahan]], [[Adam P. Goucher]] || [https://conwaylife.com/forums/viewtopic.php?p=71925#p71925]
|- class="expand-child"
| colspan="5" | A modification of [[Dean Hickerson]]'s [[cyclotron]] which uses only [[stable]] components.
|-
| 25 || 25 || [[230P8]] || [[Arie Paap]] || [https://conwaylife.com/forums/viewtopic.php?p=68099#p68099]
|- class="expand-child"
| colspan="5" | A high-clearance p8 [[domino]] sparker that can be used to create a p32 [[phase shift]] oscillator.
|-
| 26 || 23 || p250 c/10 orthogonal [[rake]] || [[Christoph Reinthaler]] || [https://conwaylife.com/forums/viewtopic.php?p=85846#p85846]
|- class="expand-child"
| colspan="5" | The lowest-period [[c/10 orthogonal]] rake constructed to date.
|-
| 27 || 19 || Hackersaw || [[Gustone]] || [https://conwaylife.com/forums/viewtopic.php?p=84247#p84247]
|- class="expand-child"
| colspan="5" | A logarithmic-growth pattern with a [[sawtooth]]-shaped population graph.
|}

===2018===
[https://conwaylife.com/forums/viewtopic.php?p=67012#p67012 Entries] • [https://conwaylife.com/forums/viewtopic.php?p=67446#p67446 Voting] • [https://conwaylife.com/forums/viewtopic.php?p=68446#p68446 Results]

The following patterns were voted on for the {{year|2018}} competition. Users were able to vote on as many patterns as they wished, awarding up to three stars to each one. [[77topaz]] organized the competition.

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Stars
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| 1 || 106 || [[Sir Robin]] || [[Adam P. Goucher]], [[Tomas Rokicki]] || [https://conwaylife.com/forums/viewtopic.php?p=57354#p57354]
|- class="expand-child"
| colspan="5" | A [[(2,1)c/6]] spaceship, and the first [[elementary spaceship|elementary]] [[oblique]] spaceship discovered in Conway's Game of Life.
|-
| 2 || 90 || [[0E0P metacell]] || [[Adam P. Goucher]] || [https://cp4space.wordpress.com/2018/11/12/fully-self-directed-replication/]
|- class="expand-child"
| colspan="5" | A [[unit cell]] which does not require a background grid of metacells to function, proving the existence of unusual classes of patterns such as quadratic [[replicator]]s and [[RRO]]s in Conway's Game of Life "imported" from other rules.
|-
| 3 || 79 || [[Reverse caber-tosser]] || [[Adam P. Goucher]], [[Dave Greene]], [[Chris Cain]] || [https://conwaylife.com/forums/viewtopic.php?p=61666#p61666]
|- class="expand-child"
| colspan="5" | A complex mechanism which theoretically allows any [[glider synthesis|glider-synthesisable]] pattern to be synthesised in just 35 gliders, by encoding the pattern's complexity into the distance between the gliders rather than their quantity.
|-
| 4 || 52 || [[Turing machine]] simulator || [[Michael Simkin]] || [https://conwaylife.com/forums/viewtopic.php?p=58910#p58910]
|- class="expand-child"
| colspan="5" | A script which can simulate arbitrary [https://en.wikipedia.org/wiki/Turing_machine Turing machines] in Conway's Game of Life using a finite tape.
|-
| 5 || 45 || [[Camelship]] || [[Chris Cain]] || [https://conwaylife.com/forums/viewtopic.php?p=66297#p66297]
|- class="expand-child"
| colspan="5" | A [[self-constructing]] [[oblique]] spaceship with the minimum possible step size for a [[slope]] 3 spaceship.
|-
| data-sort-value="6" | =6 || 41 || New [[self-constructing]] spaceships || [[Dave Greene]] || [http://b3s23life.blogspot.com/2018/11/new-tools-for-self-construction.html]
|- class="expand-child"
| colspan="5" | A [[loopship]], along with [[HashLife]]-friendly variants of [[Orthogonoid]] and [[Demonoid]].
|-
| data-sort-value="6" | =6 || 41 || c/2 diagonal [[telegraph]] [[recipe]] || [[Martin Grant]] || [https://conwaylife.com/forums/viewtopic.php?p=64489#p64489]
|- class="expand-child"
| colspan="5" | A 140-glider recipe to create a detectable c/2 diagonal [[signal]] traveling non-destructively along an arbitrarily long [[barge]] or [[ship]].
|-
| 8 || 35 || [[Period-52 glider gun]] || [[Dave Greene]], [[Matthias Merzenich]], [[Adam P. Goucher]], [[Chris Cain]], [[Entity Valkyrie]] || [https://conwaylife.com/forums/viewtopic.php?p=64083#p64083] [https://conwaylife.com/forums/viewtopic.php?p=65720#p65720] [https://conwaylife.com/forums/viewtopic.php?p=65762#p65762]
|- class="expand-child"
| colspan="5" | The first true-period 52 [[gun]] constructed, which was later [[P13-assisted period-52 glider gun|vastly reduced]] using [[53P13]].
|-
| 9 || 34 || Stable [[line crosser]] || [[Dave Greene]], [[Goldtiger997]], [[Chris Cain]] || [https://conwaylife.com/forums/viewtopic.php?p=63536#p63536]
|- class="expand-child"
| colspan="5" | A modernized rehash of a [[periodic]] circuit for transmitting a glider across a diagonal line of cells found by [[David Bell]].
|-
| data-sort-value="10" | =10 || 33 || [[Jormungant's G-to-H]] || [[Louis-François Handfield]] (Jormungant) || [https://conwaylife.com/forums/viewtopic.php?p=58814#p58814]
|- class="expand-child"
| colspan="5" | A 2G-to-H converter with a short [[recovery time]], allowing for the optimization of numerous [[gun]]s.
|-
| data-sort-value="10" | =10 || 33 || [[Period-33 glider gun]] || [[Arie Paap]], [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=64266#p64266]
|- class="expand-child"
| colspan="5" | The first true-period 33 [[gun]], which uses two interacting copies of [[Jason's p33]].
|-
| data-sort-value="10" | =10 || 33 || Infinite distinct diagonal spaceships and infinite distinct orthogonal spaceships || [[Adam P. Goucher]], [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=55400#p55400] [https://conwaylife.com/forums/viewtopic.php?p=66993#p66993]
|- class="expand-child"
| colspan="5" | Two guns which each use [[sqrtgun]] mechanisms to fire infinitely many distinct spaceships, all of which are [[puffer]]s whose outputs are eaten by spaceships arbitrarily far away.
|-
| data-sort-value="13" | =13 || 31 || Sierpinski triangle generator || [[Luka Okanishi]] || [https://conwaylife.com/forums/viewtopic.php?p=56835#p56835]
|- class="expand-child"
| colspan="5" | A [[breeder]] that outputs gliders in the shape of a growing Sierpinski triangle.
|-
| data-sort-value="13" | =13 || 31 || [[Cottonmouth]] || [[AforAmpere]] || [https://conwaylife.com/forums/viewtopic.php?p=58357#p58357]
|- class="expand-child"
| colspan="5" | An infinitely extensible [[pushalong]] for the [[copperhead]] and [[fireship]].
|-
| data-sort-value="13" | =13 || 31 || 5c/9 signal injector || [[Rhombic]], [[Simon Ekström]], [[Chris Cain]] || [https://conwaylife.com/forums/viewtopic.php?f=&p=54607#p54607]
|- class="expand-child"
| colspan="5" | A method of transforming [[Herschel]]s to [[5c/9 drifter]]s with a [[recovery time]] of 62.
|-
| 16 || 30 || [[p46 gliderless LWSS gun]] || [[Nathaniel Johnston]] || [https://conwaylife.com/forums/viewtopic.php?p=61392#p61392]
|- class="expand-child"
| colspan="5" | The smallest known [[gliderless]] [[LWSS]] gun, using three copies of [[Tanner's p46]].
|-
| data-sort-value="17" | =17 || 29 || [[Bronco]] || [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=66406#p66406]
|- class="expand-child"
| colspan="5" | The second elementary [[glider]]-to-[[Herschel]] converter to be discovered.
|-
| data-sort-value="17" | =17 || 29 || New high-period [[oscillator]]s || [[carybe]] || [https://conwaylife.com/forums/viewtopic.php?p=63969#p63969] [https://conwaylife.com/forums/viewtopic.php?p=64645#p64645] [https://conwaylife.com/forums/viewtopic.php?p=65088#p65088] [https://conwaylife.com/forums/viewtopic.php?p=65324#p65324]
|- class="expand-child"
| colspan="5" | A collective entry for [[p36 shuttle]], [[34P14 shuttle]], [[68P16]], and [[p64 thunderbird hassler]], all discovered using [[apgsearch]].
|-
| 19 || 28 || [[Quinti-Snark]]s || [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=65198#p65198]
|- class="expand-child"
| colspan="5" | Period-quintupling [[reflector]]s useful for [[gun]]s.
|-
| 20 || 27 || [[Pseudo-period]] [[xWSS]] guns || [[Chris Cain]], [[Adam P. Goucher]], [[Entity Valkyrie]], [[2718281828]], [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=65121#p65121]
|- class="expand-child"
| colspan="5" | New xWSS guns with pseudo-periods ranging from 18 to 21, breaking the previous record of 22.
|-
| 21 || 26 || [[Self-constructing]] [[oscillator]] with [[strict volatility]] one || [[Dave Greene]], [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=66216#p66216]
|- class="expand-child"
| colspan="5" | A method of constructing strictly volatile oscillators with any [[period]] 3,506,910 or above.
|-
| 22 || 25 || [[p3 bumper]] || [[Arie Paap]], [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=58869#p58869]
|- class="expand-child"
| colspan="5" | A [[periodic]] reflector to work at p39, which also allowed for the construction of a [[p57 bumper loop]]
|-
| data-sort-value="23" | =23 || 24 || Goldtiger997's Amazing 2 in 1 Reusable Multipurpose Minstrel Remover and Detector™ || [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=66828#p66828]
|- class="expand-child"
| colspan="5" | A circuit capable of removing every known [[Minstrel]] from [[Sir Robin]] at the time of its construction.
|-
| data-sort-value="23" | =23 || 24 || New mid-period [[sparker]]s || [[Dongook Lee]], [[Josh Ball]], [[Martin Grant]], [[praosylen]], [[carybe]], [[Bullet51]] || [https://conwaylife.com/forums/viewtopic.php?p=56422#p56422] [https://conwaylife.com/forums/viewtopic.php?p=58503#p58503] [https://conwaylife.com/forums/viewtopic.php?p=58616#p58616] [https://conwaylife.com/forums/viewtopic.php?p=59789#p59789] [https://conwaylife.com/forums/viewtopic.php?p=59991#p59991] [https://conwaylife.com/forums/viewtopic.php?p=62347#p62347] [https://conwaylife.com/forums/viewtopic.php?p=64284#p64284] [https://conwaylife.com/forums/viewtopic.php?p=66800#p66800]
|- class="expand-child"
| colspan="5" | A collective entry for various [[spark]]ing oscillators with periods ranging from 7 to 10, including but not limited to [[68P9]] and [[55P10]].
|-
| data-sort-value="25" | =25 || 23 || [[Minstrel 4]] || [[Entity Valkyrie]] || [https://conwaylife.com/forums/viewtopic.php?p=66748#p66748]
|- class="expand-child"
| colspan="5" | A manually-assembled [[Sir Robin]] [[tagalong]] which combines [[Minstrel]]s 1 and 3.
|-
| data-sort-value="25" | =25 || 23 || Period-doubling [[fireship]] tagalong || [[christoph.r]] || [https://conwaylife.com/forums/viewtopic.php?p=64623#p64623]
|- class="expand-child"
| colspan="5" | A [[tagalong]] for a [[flotilla]] of three [[fireship]]s which increases its period to 20.
|-
| 27 || 22 || [[p4 bouncer]] || [[Arie Paap]], [[Noam Elkies]] || [https://conwaylife.com/forums/viewtopic.php?p=64315#p64315]
|- class="expand-child"
| colspan="5" | The fastest known p4 [[reflector]].
|-
| 28 || 21 || Huge 2D-extensible [[wick]]-supporting [[pushalong]] || [[Hartmut Holzwart]] || [https://conwaylife.com/forums/viewtopic.php?p=64968#p64968]
|-
| 29 || 20 || [[Non-monotonic]] [[2c/5 orthogonal]] spaceship || [[Arie Paap]], [[Matthias Merzenich]], [[Bullet51]] || [https://conwaylife.com/forums/viewtopic.php?p=59118#p59118]
|-
| data-sort-value="30" | =30 || 19 || [[p9 bouncer]] || [[Matthias Merzenich]], [[carybe]], [[Noam Elkies]] || [https://conwaylife.com/forums/viewtopic.php?p=64309#p64309]
|- class="expand-child"
| colspan="5" | A [[reflector]] capable of reflecting a p27 glider stream using [[68P9]], which was found using [[apgsearch]] the same day.
|-
| data-sort-value="30" | =30 || 19 || p6 180-degree [[reflector]] and related [[gun]]s || [[Arie Paap]], [[Tanner Jacobi]], [[Louis-François Handfield]] || [https://conwaylife.com/forums/viewtopic.php?p=65060#p65060] [https://conwaylife.com/forums/viewtopic.php?p=65819#p65819]
|- class="expand-child"
| colspan="5" | A reflector which can be used alongside other [[sparker]]s to create arbitrary guns with period (60n+30).
|-
| 32 || 18 || Fast universal [[regulator]]s || [[Dave Greene]] || [https://conwaylife.com/forums/viewtopic.php?p=61746#p61746]
|-
| 33 || 17 || [[42883M]] || [[Adam P. Goucher]] || [https://conwaylife.com/forums/viewtopic.php?p=66055#p66055]
|- class="expand-child"
| colspan="5" | A {{times|16|16}} [[soup]] found by [[apgsearch]], and the longest-lasting known [[methuselah]] fitting within a {{times|16|16}} bounding box.
|-
| 34 || 10 || New [[honey farm]] [[hassle]]rs || [[Tanner Jacobi]], [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=65000#p65000] [https://conwaylife.com/forums/viewtopic.php?p=65021#p65021] [https://conwaylife.com/forums/viewtopic.php?p=65117#p65117]
|- class="expand-child"
| colspan="5" | A collective entry for a few [[oscillator]]s of periods 36 and 40 which use honey farm-hassling reactions.
|}

===2017===
[https://conwaylife.com/forums/viewtopic.php?p=54485#p54485 Entries] • [https://conwaylife.com/forums/viewtopic.php?p=55444#p55444 Voting] • [https://conwaylife.com/forums/viewtopic.php?p=56715#p56715 Results]

The following patterns were voted on for the {{year|2017}} competition. Users were able to vote on as many patterns as they wished, awarding up to three stars to each one. [[Adam P. Goucher]] organized the competition.

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Stars
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| 1 || 50 || [[2-engine Cordership]] || [[praosylen]] || [https://conwaylife.com/forums/viewtopic.php?p=54444#p54444]
|- class="expand-child"
| colspan="5" | A successful refutation of the common belief that 3 engines are required to build a [[Cordership]].
|-
| 2 || 34 || [[Tanner's p46]] || [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=52220#p52220]
|- class="expand-child"
| colspan="5" | A new sparky {{period|46}} [[oscillator]] that various [[gun]]s can be made from.
|-
| 3 || 32 || [[Stable pulse-divider]]s || [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=50677#p50677] [https://conwaylife.com/forums/viewtopic.php?p=52335#p52335] [https://conwaylife.com/forums/viewtopic.php?p=52636#p52636]
|- class="expand-child"
| colspan="5" | The [[Snark]] and [[semi-Snark]] have been joined by new exciting [[tremi-Snark]], [[quadri-Snark]], and [[semi-cenark]]s, which are particularly helpful for optimising [[glider gun|glider]] and spaceship [[gun]]s.
|-
| 4 || 29 || New [[Demonoid]] and [[Orthogonoid]] [[spaceship]]s || [[Dave Greene]], [[slmake]] || [https://conwaylife.com/forums/viewtopic.php?p=45264#p45264] [https://conwaylife.com/forums/viewtopic.php?p=45486#p45486]
|- class="expand-child"
| colspan="5" | [[Geminoid]] variants which travel diagonally and orthogonally, respectively, showcasing interesting developments such as [[MWSS]]-based [[signal]]ling and [[syringe]] syntheses.
|-
| 5 || 27 || The efficient {{slcells|16|text=16-bit}} still life [[synthesis]] project || [[Chris Cain]], [[BlinkerSpawn]], [[Luka Okanishi]], [[Martin Grant]], [[Matthias Merzenich]], [[Bob Shemyakin]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=38489#p38489] [https://conwaylife.com/forums/viewtopic.php?p=43734#p43734]
|- class="expand-child"
| colspan="5" | All still-lifes of 16 or fewer cells can be constructed at a cost of <= 1 glider per cell.
|-
| 6 || 26 || Synthesis of [[25P3H1V0.2]], and reductions of many other small spaceships || [[Martin Grant]], [[Chris Cain]], [[2718281828]], [[gmc_nxtman]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=54359#p54359] [https://conwaylife.com/forums/viewtopic.php?p=46308#p46308] [https://conwaylife.com/forums/viewtopic.php?p=52614#p52614] [https://conwaylife.com/forums/viewtopic.php?p=53496#p53496]
|-
| data-sort-value="7" | =7 || 24 || [[Cordership#Sparse Cordership|Sparse Cordership]] || [[David Bell]] || [https://conwaylife.com/forums/viewtopic.php?p=54103#p54103]
|- class="expand-child"
| colspan="5" | All previously-known [[Cordership]]s required interactions between two or more adjacent [[switch engine]]s. This design, on the other hand, allows the individual switch engines to be separated by arbitrary distances, relying instead on long-range interactions mediated by [[glider]]s and [[stable]] objects.
|-
| data-sort-value="7" | =7 || 24 || [[Hydra]] || [[Oscar Cunningham]], [[Dave Greene]], [[slmake]] || [https://conwaylife.com/forums/viewtopic.php?p=53089#p53089]
|- class="expand-child"
| colspan="5" | A [[single-channel]] [[quadratic-growth]] pattern which constructs an intricate mesh of splitting construction heads in all directions. Some well-positioned [[eater]]s prevent this behemoth from cannibalising itself. It uses similar technology to Dave's earlier triple wickstretcher, but is more complex owing to the necessity of splitting signals.
|-
| 9 || 22 || [[3-glider collision|Three-glider synthesis]] of a [[switch engine]] || [[Luka Okanishi]] || [https://conwaylife.com/forums/viewtopic.php?p=41557#p41557]
|- class="expand-child"
| colspan="5" | It was previously believed that 4 gliders were necessary and sufficient to synthesise a switch engine.
|-
| 10 || 21 || Synthesis of ''N''-bit still lifes in 38 to 39 gliders || [[Tanner Jacobi]], [[Adam P. Goucher]], [[Chris Cain]] || [https://conwaylife.com/forums/viewtopic.php?p=40503#p40503] [https://conwaylife.com/forums/viewtopic.php?p=40526#p40526]
|- class="expand-child"
| colspan="5" | [[Glider synthesis|Syntheses]] of ''N''-bit still lifes for all sufficiently large natural numbers ''N'', using a bounded number of [[glider]]s (38 or 39, depending on the parity of ''N'').
|-
| 11 || 18 || Life object having a bounded population with an [[unknown fate]] || [[David Bell]] || [https://conwaylife.com/forums/viewtopic.php?p=53533#p53533]
|- class="expand-child"
| colspan="5" | [[Collatz 5n+1 simulator|A pattern]] which either becomes [[stable]], [[oscillator]]y, or aperiodic, depending on the behaviour of 7 under the generalised Collatz iteration which maps a positive integer ''N'' to 5''N''+1 (if ''N'' odd) or ''N''/2 (if ''N'' even).
|-
| data-sort-value="12" | =12 || 17 || Completed [[Quest for Tetris]] challenge || [[PhiNotPi]], [[El'endia Starman]], [[K Zhang]], [[Muddyfish]], [[Kritixi Lithos]], [[Mego]], [[Quartata]], et al. || [https://codegolf.stackexchange.com/questions/11880/build-a-working-game-of-tetris-in-conways-game-of-life/142673#142673]
|- class="expand-child"
| colspan="5" | A game of Tetris simulated on a digital computer built out of logic gates formed from [[Brice Due]]'s [[metacell]]s.
|-
| data-sort-value="12" | =12 || 17 || [[Gliderless]] [[unit cell]] || [[Peter Naszvadi]] || [https://conwaylife.com/forums/viewtopic.php?p=53026#p53026]
|- class="expand-child"
| colspan="5" | A cellular automata [[polyglot]] (pattern which runs in a range of rules) based on p46 technology, establishing Turing-completeness of B3[8]/S23[8] provided infinite patterns are permitted.
|-
| data-sort-value="12" | =12 || 17 || [[Garden of Eden 11]] || [[Steven Eker]] || [http://wwwhomes.uni-bielefeld.de/achim/orphan_11th.html]
|- class="expand-child"
| colspan="5" | An [[orphan]] with 45 live cells and 43 dead cells, the fewest total number of specified cells among all known orphans.
|-
| 15 || 16 || Several new [[stable]] [[signal]] [[converter]]s || [[Dave Greene]], [[Goldtiger997]] || [https://conwaylife.com/forums/viewtopic.php?p=42465#p42465]
|-
| 16 || 15 || [[339P7H1V0]] || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=40206#p40206]
|- class="expand-child"
| colspan="5" | The narrowest odd-symmetric c/7 spaceship, and the second known [[elementary]] c/7 spaceship, after the [[loafer]].
|-
| 17 || 14 || Much smaller [[spiral growth]] pattern || [[Dave Greene]], [[slmake]] || [https://conwaylife.com/forums/viewtopic.php?p=44792#p44792]
|- class="expand-child"
| colspan="5" | A tightly-coiled loop of data reflected in a double-spiral of [[Snark]]s instructs a [[construction arm]] to encircle the construction indefinitely, gradually constructing an unbounded spiral of further Snarks.
|-
| 18 || 13 || p148 B29 gun || [[Luka Okanishi]], [[Dave Greene]], [[Adam P. Goucher]] || [https://conwaylife.com/forums/viewtopic.php?p=40764#p40764]
|- class="expand-child"
| colspan="5" | A compact [[gun]] for a [[B29|c/4 diagonal spaceship]].
|-
| data-sort-value="19" | =19 || 12 || Cumulative sum generator || [[gameoflifeboy]] || [https://conwaylife.com/forums/viewtopic.php?p=40837#p40837]
|-
| data-sort-value="19" | =19 || 12 || Triple wickstretcher || [[Dave Greene]] || [https://conwaylife.com/forums/viewtopic.php?p=44377#p44377]
|- class="expand-child"
| colspan="5" | A [[single-channel]] [[glider loop]] which extends zigzags of [[Snark]]s.
|-
| data-sort-value="19" | =19 || 12 || The first 3c/7 orthogonal puffer || [[Luka Okanishi]] || [https://conwaylife.com/forums/viewtopic.php?p=41074#p41074]
|- class="expand-child"
| colspan="5" | Exclusively using 3c/7 [[spaghetti monster]]s (the only known spaceship of its velocity). Owing to its faster-than-c/4 speed, a c/2 spaceship is necessary to catch up with the front of the engine to continue the reaction.
|-
| 22 || 11 || The first c/6 orthogonal puffers || [[Nico Brown]], [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=47306#p47306]
|- class="expand-child"
| colspan="5" | Messy albeit elegant [[puffer]]s where [[glider]]s collide with large sparky spaceships in perpetuity.
|-
| 23 || 9 || Fixed-length [[tail]] for a [[lightspeed bubble]] of arbitrary width in the [[zebra stripes]] [[agar]] || [[Arie Paap]] || [https://conwaylife.com/forums/viewtopic.php?p=40615#p40615]
|- class="expand-child"
| colspan="5" | [[Gabriel Nivasch]] showed that arbitrary-width lightspeed bubbles in the zebra stripes agar are supportable, requiring a fixed-length head and variable-length tail. It was hitherto an open problem to replace the variable-length tail with a fixed-length counterpart.
|-
| 24 || 7 || [[28P7.3]] || [[Bullet51]] || [https://conwaylife.com/forums/viewtopic.php?p=54236#p54236]
|- class="expand-child"
| colspan="5" | The smallest known (tied with previous record) {{period|7}} [[oscillator]].
|-
| 25 || 6 || [[Runny nose]] || [[83bismuth38]] || [https://conwaylife.com/forums/viewtopic.php?p=41272#p41272]
|- class="expand-child"
| colspan="5" | A {{period|3}} [[oscillator]] which showed an unexpected gap in lists of small objects.
|}

===2016===
[https://conwaylife.com/forums/viewtopic.php?p=39117#p39117 Entries] • [https://conwaylife.com/forums/viewtopic.php?p=41977#p41977 Voting] • [https://conwaylife.com/forums/viewtopic.php?p=44028#p44028 Results]

The following patterns were voted on for the {{year|2016}} competition. Users were able to vote on as many patterns as they wished, awarding up to three stars to each one. [[Alexey Nigin]] organized the competition.

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Stars
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| 1 || 49 || [[Caterloopillar]]s || [[Michael Simkin]], [[David Bell]] et al. || [https://conwaylife.com/forums/viewtopic.php?p=29796#p29796]
|- class="expand-child"
| colspan="5" | Previously, all [[engineered spaceship]]s had speeds that were either fixed ([[Caterpillar]]) or adjustable but always very low ([[Gemini]]). Caterloopillars have the best of both worlds: their speed is variable, and the fastest ones can travel as quickly as c/4. So far all caterloopillars have been orthogonal, but a project to build one with adjustable [[slope]] is underway.
|-
| 2 || 47 || [[Copperhead]] || [[zdr]], [[Simon Ekström]] et al. || [https://conwaylife.com/forums/viewtopic.php?p=27988#p27988] [https://conwaylife.com/forums/viewtopic.php?p=28956#p28956]
|- class="expand-child"
| colspan="5" | In addition to being the first of its speed, this [[c/10 orthogonal]] [[spaceship]] is so small that it is surprising nobody discovered it before. Its small size allowed the creation of a 22-glider synthesis, and a gun was made soon afterwards. A pseudo-tagalong known as the [[fireship]] found a bit later made it possible to create c/10 [[puffers]] and [[rakes]]. Much of copperhead's fame is due to the mystery surrounding its discovery: it was posted by a newly-joined anonymous user who became inactive afterwards.
|-
| 3 || 39 || [[Grandfather problem|Grandfather-less Pattern]] || [[mtve]] || [https://conwaylife.com/forums/viewtopic.php?p=30646#p30646]
|- class="expand-child"
| colspan="5" | "Is there a configuration which has a father but no grandfather?" This is the statement of the grandfather problem, one of the longest-standing open problems in [[Conway's Game of Life|Life]], having been unsolved for decades in spite of a $50 prize offer from [[John Conway]] Himself in September 1972. It was only this year that the first grandfather-less pattern was discovered using a SAT solver.
|-
| 4 || 31 || [[Spaghetti monster]] || [[Tim Coe]] || [https://conwaylife.com/forums/viewtopic.php?p=31863#p31863]
|- class="expand-child"
| colspan="5" | This is the first spaceship with a speed of 3c/7, which has been one of the most sought-after speeds in the last 15 years. The ship was discovered with [[knightt]], a relatively new search program. The search took about two months, even though the width was continuously tweaked to make it faster.
|-
| 5 || 28 || [[8-bit computer]] || [[Coban]] || [https://conwaylife.com/forums/viewtopic.php?p=37428#p37428]
|- class="expand-child"
| colspan="5" | This is the first 8-bit computer in any [[cellular automaton]], and easily the most realistic computer ever constructed in Life. It has a ROM which contains the program, consisting of 32 instructions which are stored in 21 bits each. For RAM, it has a register bank containing eight 8-bit registers. For output, it has a "printer" with 8 pixels.
|-
| 6 || 19 || [[Herschel splitter]] || [[Luka Okanishi]] || [https://conwaylife.com/forums/viewtopic.php?p=29968#p29968]
|- class="expand-child"
| colspan="5" | This is an elegant solution to an old circuitry problem: a direct [[Herschel]] signal splitter that recovers in less than a hundred ticks. People had been looking for something exactly like this for very nearly twenty years, ever since the original 1996-97 universal set of [[Herschel conduit]]s. It was made by extending an [[Fx119]] conduit with a partial copy of itself to extract the second Herschel output.
|-
| 7 || 14 || [[Bumper]] || [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=29711#p29711]
|- class="expand-child"
| colspan="5" | This [[reflector]] mechanism can be attached to a variety of sparky [[oscillator]]s to make reflectors of the corresponding periods. Since the resulting reflectors have different timing than the [[Snark]], they solve a range of "my glider is in the wrong phase" wiring problems. A small wave of record-breaking guns followed soon after the bumper's debut.
|-
| data-sort-value="8" | =8 || 12 || New gun periods || [[Luka Okanishi]], [[Maia Karpovich]], [[Matthias Merzenich]], [[Chris Cain]] || [https://conwaylife.com/forums/viewtopic.php?p=29965#p29965] [https://conwaylife.com/forums/viewtopic.php?p=29991#p29991] [https://conwaylife.com/forums/viewtopic.php?p=30033#p30033]
|- class="expand-child"
| colspan="5" | In three days, three new true gun periods were discovered: [[Period-61 glider gun|p61]], [[Period-58 glider gun|p58]], and [[Period-57 glider gun|p57]].
|-
| data-sort-value="8" | =8 || 12 || [[Statorless p5]] || [[Josh Ball]] || [https://conwaylife.com/forums/viewtopic.php?p=32242#p32242]
|- class="expand-child"
| colspan="5" | This is the first [[statorless]] oscillator of its period. Since the period is prime, the lack of stator implies that the oscillator is [[strictly volatile]], which is a rare property.
|-
| 10 || 11 || Aperiodic tiles || [[NotLiving]] || [https://conwaylife.com/forums/viewtopic.php?p=30640#p30640]
|- class="expand-child"
| colspan="5" | This is an implementation of a particular set of [https://en.wikipedia.org/wiki/Wang_tiles Wang tiles] in the Game of Life. The Life tiles form a stable pattern if and only if the corresponding arrangement of Wang tiles is valid. Since this set of Wang tiles can only form aperiodic arrangements, so can the Life tiles.
|-
| 11 || 10 || [[Rich's p16]] || [[Rich Holmes]] || [https://conwaylife.com/forums/viewtopic.php?p=32766#p32766]
|- class="expand-child"
| colspan="5" | This is a small [[:Category:Oscillators with period 16|p16]] oscillator that appeared [[natural]]ly. It is compact for its period and has easily accessible [[spark]]s. Most notably, it can filter [[glider]] streams similarly to the [[blocker]], which led to reductions in many guns that previously utilized other filter mechanisms.
|-
| 12 || 9 || Small [[Garden of Eden|GoE]]s || [[Steven Eker]] || [http://wwwhomes.uni-bielefeld.de/achim/orphan_9th.html] [http://wwwhomes.uni-bielefeld.de/achim/orphan_10th.html]
|- class="expand-child"
| colspan="5" | A few record-breaking Gardens of Eden and [[orphan]]s were found, including an orphan with only 89 defined cells.
|-
| data-sort-value="13" | =13 || 6 || 15-bit [[still life]] [[syntheses]] || [[BlinkerSpawn]], [[Goldtiger997]], [[Bob Shemyakin]], [[Mark Niemiec]], [[Martin Grant]], [[Chris Cain]], et al. || [https://conwaylife.com/forums/viewtopic.php?p=36803#p36803] [https://conwaylife.com/forums/viewtopic.php?p=37438#p37438]
|- class="expand-child"
| colspan="5" | A project to find syntheses of all {{slcells|15|text=15-bit}} still lifes in under 15 gliders turned out to be a very prolific collaboration. Using [[Catagolue]] soups along with known and new [[converter]] mechanisms, several hundred new syntheses were created. The goal was achieved in just 41 days.
|-
| data-sort-value="13" | =13 || 6 || [[132P7|p7 sparker]] || [[Dongook Lee]] || [https://conwaylife.com/forums/viewtopic.php?p=38352#p38352]
|- class="expand-child"
| colspan="5" | This pattern adds a new relatively strong [[heavyweight emulator]] to the p7 collection, which previously only had the [[pipsquirter]]. It was used to complete a p28 [[wick]] with no prior stabilization.
|}

===2015===
[https://conwaylife.com/forums/viewtopic.php?p=26338#p26338 Entries] • [https://conwaylife.com/forums/viewtopic.php?p=26648#p26648 Voting] • [https://conwaylife.com/forums/viewtopic.php?p=27344#p27344 Results]

The following patterns were voted on for the {{year|2015}} competition. Users chose as many pattern as they wanted and ranked them from best to worst; the votes were then tallied with a custom Delphi program.<ref name="post27345" /> Alexey Nigin organized the competition.

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Points
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| 1 || 107 || [[Syringe]] || [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=18086#p18086]
|- class="expand-child"
| colspan="5" | Syringe is the fast [[glider|G]]-to-[[Herschel|H]] that Herschel plumbers have been wishing for a decade, also allowing for fast signal splitters and other much more efficient logic circuits, including self-constructing circuitry.
|-
| 2 || 102 || [[Simkin glider gun]] || [[Michael Simkin]] || [https://conwaylife.com/forums/viewtopic.php?p=19124#p19124]
|- class="expand-child"
| colspan="5" | The [[Simkin glider gun]] is the smallest gun ever constructed. The previous record holder, the [[Gosper glider gun]], was constructed as long ago as {{year|1970}}.
|-
| 3 || 91 || [[Demonoid]]s || [[Chris Cain]] and [[Dave Greene]] || [https://conwaylife.com/forums/viewtopic.php?p=25401#p25401] [https://conwaylife.com/forums/viewtopic.php?p=25702#p25702]
|- class="expand-child"
| colspan="5" | Demonoids are highly-simplified, diagonally-moving variants of the original [[Gemini]] spaceship. The 0hd Demonoid is the only case where a spaceship [[gun]] pattern was completed before the actual spaceship.
|-
| 4 || 55 || Syntheses of [[spaceship]]s || [[Martin Grant]], [[Tanner Jacobi]], and [[Chris Cain]] || [https://conwaylife.com/forums/viewtopic.php?p=15474#p15474] [https://conwaylife.com/forums/viewtopic.php?p=15747#p15747] [https://conwaylife.com/forums/viewtopic.php?p=15951#p15951] [https://conwaylife.com/forums/viewtopic.php?p=16223#p16223] [https://conwaylife.com/forums/viewtopic.php?p=16736#p16736] [https://conwaylife.com/forums/viewtopic.php?p=17576#p17576] [https://conwaylife.com/forums/viewtopic.php?p=18531#p18531] [https://conwaylife.com/forums/viewtopic.php?p=20360#p20360] [https://conwaylife.com/forums/viewtopic.php?p=22469#p22469]
|- class="expand-child"
| colspan="5" | Syntheses of [[B29]], [[X66]], half-X66 with [[HWSS]], [[Pushalong 1]], [[25P3H1V0.2]], [[30P5H2V0]], [[30P4H2V0]], a pufferfish spaceship, and the [[weekender]] were discovered in 2015, which exceeds the number of spaceship syntheses found in any previous year, including 1970.
|-
| 5 || 48 || [[Recursive filter]] || [[Alexey Nigin]] and [[Kiran Linsuain]] || [https://conwaylife.com/forums/viewtopic.php?p=20935#p20935]
|- class="expand-child"
| colspan="5" | [https://conwaylife.com/forums/viewtopic.php?p=20935#p20935 Recursive Filter] allows the creation of extremely slow-growing patterns. A single recursive filter gives the growth rate of [https://en.wikipedia.org/wiki/Iterated_logarithm log*(t)], which is slower than the growth rate of any pattern constructed before. Recursive filters can be stacked to obtain even more mind-boggling growth rates.
|-
| 6 || 45 || [[Glider]]-to-[[Weekender]] || [[Chris Cain]] || [https://conwaylife.com/forums/viewtopic.php?p=23009#p23009]
|- class="expand-child"
| colspan="5" | [https://conwaylife.com/forums/viewtopic.php?p=23009#p23009 G-to-Weekender] splits a single input [[glider]] into 82 separate signals, and successfully synchronizes them to produce an output [[weekender]] spaceship. The previous record synchronization was [[Adam P. Goucher|Goucher]]'s glider-to-[[Cordership]] converter, which produced 19 synchronized gliders from one input signal.
|-
| 7 || 34 || [[Bob Shemyakin]]'s syntheses || [[Bob Shemyakin]] || [https://conwaylife.com/forums/viewtopic.php?p=23931#p23931]
|- class="expand-child"
| colspan="5" | [https://conwaylife.com/forums/viewtopic.php?p=23931#p23931 Bob Shemyakin's syntheses] are often cheaper than what could be found in [[Mark Niemiec]]'s database (and those were already pretty good). This was the result of a lot of patient script-writing and collecting collision results, starting with adding two gliders (within a certain range) to every possible two-glider collision. Many new 4-, 5-, and 6-glider still life recipes were found, and optimizations for many larger still lifes up to 15 bits.
|-
| 8 || 33 || [[HBK gun]] || [[Chris Cain]] and [[Michael Simkin]] || [https://conwaylife.com/forums/viewtopic.php?p=15639#p15639]
|- class="expand-child"
| colspan="5" | HBK gun is an extremely large and complex [[gun]] that fires parallel HBKs. It is the only gun to produce non-self-constructing macro-spaceships.
|-
| 9 || 31 || [[Herschel-to-MWSS]] || [[Tanner Jacobi]] || [https://conwaylife.com/forums/viewtopic.php?p=23888#p23888]
|- class="expand-child"
| colspan="5" | [https://conwaylife.com/forums/viewtopic.php?p=23888#p23888 H-to-MWSS] is the smallest converter of [[Herschel]]s into (non-[[glider]]) [[standard spaceship]]s. Prior constructions of XWSSs required many [[Herschel track]]s and a large area.
|-
| 10 || 30 || [[Sawtooth 177]] || [[Maia Karpovich]], [[Tanner Jacobi]], [[Chris Cain]], [[Adam P. Goucher]], and [[Dave Greene]] || [https://conwaylife.com/forums/viewtopic.php?p=24245#p24245]
|- class="expand-child"
| colspan="5" | Sawtooth 177 is currently the smallest known sawtooth.
|-
| 11 || 29 || [[Single-lane construction arm toolkit]] || [[Simon Ekström]] || [https://conwaylife.com/forums/viewtopic.php?p=26024#p26024]
|- class="expand-child"
| colspan="5" | The [https://conwaylife.com/forums/viewtopic.php?p=26024#p26024 Single-Lane Construction Arm Toolkit] is an important result for simplifying [[self-constructing]] [[circuitry]], especially those where a recipe needs to be duplicated, as in the [[linear propagator]], not just interpreted as in the [[Demonoid]] and [[Gemini]].
|-
| 12 || 28 || Elementary conduits collection || [[Matthias Merzenich]], [[Dave Greene]], and [[Maia Karpovich]] || [https://conwaylife.com/forums/viewtopic.php?p=25684#p25684]
|- class="expand-child"
| colspan="5" | The [https://conwaylife.com/forums/viewtopic.php?p=25684#p25684 Elementary Conduits Collection], recently significantly expanded with new discoveries, is a one-stop shop for the building blocks of [[stable]] [[track]]s. It was organized to catalogue all [[converter]]s between likely active reactions, not just from [[Herschel]] to Herschel.
|-
| 13 || 26 || [[45-degree MWSS-to-G|(L{{!}}M)WSS-to-glider]] || [[Ivan Fomichev]] and [[Dongook Lee]] || [https://conwaylife.com/forums/viewtopic.php?p=23800#p23800]
|- class="expand-child"
| colspan="5" | [https://conwaylife.com/forums/viewtopic.php?p=23800#p23800 (L|M)WSS-to-G] is the second known small conduit that turns [[standard spaceship]]s into [[glider]]s, and the first that accepts [[LWSS]]s.
|-
| 14 || 23 || Collection of guns || [[Chris Cain]], [[Simon Ekström]], [[Scot Ellison]], and [[Dave Greene]] || [https://github.com/ceebo/glider_guns]
|- class="expand-child"
| colspan="5" | The [https://github.com/ceebo/glider_guns Collection of Guns] is an ambitious project to collect new smaller [[glider gun]]s using the [[syringe]] and other recent discoveries. All guns in the range 78-999 were eventually reduced to bounding boxes less than 8000 cells.
|-
| 15 || 19 || [[Dragon lightsaber]] || [[Martin Grant]] || [https://conwaylife.com/forums/viewtopic.php?p=18503#p18503]
|- class="expand-child"
| colspan="5" | [https://conwaylife.com/forums/viewtopic.php?p=18503#p18503 Dragon Lightsaber] is a mysterious pattern that seems to calculate some sequence. It is [https://xkcd.com/1433/ this] type of a lightsaber.
|-
| 16 || 14 || [[Quadratic sawtooth]] || [[Martin Grant]], [[praosylen]], [[Dongook Lee]], and [[Alexey Nigin]] || [https://conwaylife.com/forums/viewtopic.php?p=19443#p19443]
|- class="expand-child"
| colspan="5" | [https://conwaylife.com/forums/viewtopic.php?p=19443#p19443 Quadratic sawtooth] is a [[sawtooth]] whose population peaks grow quadratically.
|-
| 17 || 13 || [[Tlog(log(t)) growth|t*log(log(t)) growth]] || [[Alexey Nigin]] and [[Michael Simkin]] || [https://conwaylife.com/forums/viewtopic.php?p=19959#p19959]
|- class="expand-child"
| colspan="5" | [https://conwaylife.com/forums/viewtopic.php?p=19959#p19959 t*log(log(t)) growth] is pattern with an exotic growth rate. That growth rate has long been achievable via [[exponential filter]]s, but this pattern utilizes a completely different design.
|}

===2014===
[https://conwaylife.com/forums/viewtopic.php?p=27369#p27369 Initial entries] • [https://conwaylife.com/forums/viewtopic.php?p=56723#p56723 Belated entries] • [https://conwaylife.com/forums/viewtopic.php?p=56796#p56796 Belated voting] • [https://conwaylife.com/forums/viewtopic.php?p=57457#p57457 Results]

The following patterns were submitted as competition entries by users in early 2016. Patterns were not voted on at the time, but a belated vote was held in early 2018, featuring three further submissions in addition to the original nine. [[Kiran Linsuain]] organized the 2016 competition; [[77topaz]] organized the 2018 vote.

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Stars
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| 1 || 30 || [[Waterbear]] || [[Brett Berger]] and [[Ivan Fomichev]] || [https://conwaylife.com/forums/viewtopic.php?p=15284#p15284]
|- class="expand-child"
| colspan="5" | The first fast oblique [[spaceship]], moving at speed (23,5)c/79.
|-
| 2 || 23 || [[Centipede]] || [[Chris Cain]] || [https://conwaylife.com/forums/viewtopic.php?p=13070#p13070]
|- class="expand-child"
| colspan="5" | A large, engineered [[spaceship]] that moves at 31c/240, using a unique reaction.
|-
| 3 || 21 || [[Half-baked knightship]] || [[Adam P. Goucher]], [[Chris Cain]], [[Dave Greene]], and [[Ivan Fomichev]] || [https://conwaylife.com/forums/viewtopic.php?p=12630#p12630]
|- class="expand-child"
| colspan="5" | An oblique [[spaceship]] that moves with [[displacement]] (6,3), using the [[half-bakery reaction]].
|-
| data-sort-value="4" | =4 || 17 || [[Switch engine ping-pong]] || [[Michael Simkin]] || [https://conwaylife.com/forums/viewtopic.php?p=14050#p14050]
|- class="expand-child"
| colspan="5" | A 23-cell [[quadratic growth]] pattern, the smallest known.
|-
| data-sort-value="4" | =4 || 17 || Syntheses for all {{slcells|17|text=17-bit}} and {{slcells|18|text=18-bit}} [[still life]]s || [[Martin Grant]], [[Mark Niemiec]], and [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=11972#p11972] [https://conwaylife.com/forums/viewtopic.php?p=14272#p14272]
|- class="expand-child"
| colspan="5" | Note: Some of the 18-bit syntheses were later found to be invalid, and the project was not completed for real until 2019.<ref name="post83979" />
|-
| data-sort-value="6" | =6 || 13 || [[Pufferfish]] || [[Richard Schank]] || [https://conwaylife.com/forums/viewtopic.php?p=14510#p14510]
|- class="expand-child"
| colspan="5" | A [[period]] 12 c/2 [[puffer]] that was used to make the first wholly high-period c/2 spaceship.
|-
| data-sort-value="7" | =6 || 13 || [[Spiral growth]] || [[Dave Greene]] || [https://conwaylife.com/forums/viewtopic.php?p=12815#p12815]
|- class="expand-child"
| colspan="5" | A [[self-constructing pattern]] that grows in an outward spiral.
|-
| data-sort-value="8" | =8 || 12 || [[Dart]] and [[crab]] syntheses || [[Martin Grant]], [[Mark Niemiec]], [[Michael Simkin]], [[Ivan Fomichev]], [[Tanner Jacobi]], and [[Brett Berger]] || [https://conwaylife.com/forums/viewtopic.php?p=14680#p14680] [https://conwaylife.com/forums/viewtopic.php?p=15243#p15243]
|- class="expand-child"
| colspan="5" | [[Glider synthesis|Glider syntheses]] for small [[spaceship]]s that did not previously have any.
|-
| data-sort-value="8" | =8 || 12 || [[Weekender distaff]] || [[Ivan Fomichev]] || [https://conwaylife.com/forums/viewtopic.php?p=12047#p12047]
|- class="expand-child"
| colspan="5" | The first 2c/7 orthogonal [[rake]], consisting of a long chain of [[weekender]]s perturbing [[ash|debris]].
|-
| 10 || 8 || [[Honey thieves]]&dagger; || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=13179#p13179]
|- class="expand-child"
| colspan="5" | The smallest known {{period|17}} [[oscillator]], and the first one with a known [[glider synthesis]].
|-
| 11 || 7 || p27 [[billiard table]] oscillator&dagger; || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=13248#p13248]
|- class="expand-child"
| colspan="5" | An [[oscillator]] in which period 5, period 8 and period 3 [[rotor]]s [[phase shift]] each other.
|-
| 12 || 6 || [[LCM oscillators]]&dagger; || [[Noam Elkies]] || [https://conwaylife.com/forums/viewtopic.php?p=56725#p56725]
|- class="expand-child"
| colspan="5" | [[Oscillator]]s featuring multiple [[rotor]]s that interact in complicated ways.
|}

&dagger;not originally submitted in 2014.

===2013===
[https://conwaylife.com/forums/viewtopic.php?p=57472#p57472 Entries] • [https://conwaylife.com/forums/viewtopic.php?p=57924#p57924 Voting] • [https://conwaylife.com/forums/viewtopic.php?p=58573#p58573 Results]

No competition was initially held in {{year|2013}}. However, it was mentioned in [https://conwaylife.com/forums/viewtopic.php?p=7826#p7826 various] [https://conwaylife.com/forums/viewtopic.php?p=26363#p26363 places] that the winner for 2013 was clearly Mike Playle's [[Snark]], with no particular need for a formal vote. A belated vote was organized in early {{year|2018}} by [[77topaz]]. The following patterns were submitted as competition entries by users.

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Stars
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| 1 || 34 || [[Snark]] || [[Mike Playle]] || [https://conwaylife.com/forums/viewtopic.php?p=7819#p7819]
|- class="expand-child"
| colspan="5" | A [[stable]] 90˚ glider [[reflector]] which, with 52 cells and a [[repeat time]] of 43, is both far smaller and far faster than previous such patterns.
|-
| 2 || 31 || [[Loafer]] || [[Josh Ball]] || [https://conwaylife.com/forums/viewtopic.php?p=7450#p7450]
|- class="expand-child"
| colspan="5" | The first [[c/7 orthogonal]] spaceship and, with just 20 cells, the smallest spaceship other than the glider and [[xWSS]]es.
|-
| data-sort-value="3" | =3 || 22 || [[CC semi-Snark]] || [[Sergey Petrov]] || [https://conwaylife.com/forums/viewtopic.php?p=8383#p8383]
|- class="expand-child"
| colspan="5" | A small, [[Spartan]] 90˚ glider reflector which functions as a [[period doubler]].
|-
| data-sort-value="3" | =3 || 22 || [[Linear propagator]] || [[Dave Greene]] || [https://conwaylife.com/forums/viewtopic.php?p=9901#p9901]
|- class="expand-child"
| colspan="5" | A large, engineered pattern which is arguably the first example of a [[replicator]] in Conway's Game of Life, depending on the exact definition used.
|-
| 5 || 17 || Original 16-bit [[still life]] [[synthesis]] project || [[Martin Grant]], [[Mark Niemiec]], [[Matthias Merzenich]], [[Dave Greene]] || [https://conwaylife.com/forums/viewtopic.php?p=10227#p10227]
|- class="expand-child"
| colspan="5" | A project to synthesize all 16-bit still lifes.
|-
| 6 || 15 || [[Period-20 glider gun]] || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=7975#p7975]
|- class="expand-child"
| colspan="5" | A true period-20 [[glider gun]], the smallest true period known for a gun.
|-
| 7 || 14 || [[135-degree MWSS-to-G]] || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=8489#p8489]
|- class="expand-child"
| colspan="5" | The first fast [[elementary]] [[MWSS]]-to-[[glider]] [[converter]].
|-
| 8 || 11 || [[Period-40 glider gun]] || [[Adam P. Goucher]], [[Matthias Merzenich]], [[Jason Summers]] || [https://conwaylife.com/forums/viewtopic.php?p=7594#p7594]
|- class="expand-child"
| colspan="5" | A true period-40 [[glider gun]] based on complicated reactions involving [[honey farm]] predecessors, {{period|5}} and {{period|8}} [[oscillator]]s.
|-
| data-sort-value="9" | =9 || 9 || [[AK-94]] and [[Pre-pulsar shuttle]] 22 || [[Mike Playle]], [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=7954#p7954] [https://conwaylife.com/forums/viewtopic.php?p=7961#p7961]
|- class="expand-child"
| colspan="5" | Two constructions based on a new [[catalyst]] found by [[Mike Playle]].
|-
| data-sort-value="9" | =9 || 9 || [[Standard spaceship]] [[eater]] || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=8579#p8579]
|- class="expand-child"
| colspan="5" | A [[still life]] capable of [[eater|eating]] every type of [[standard spaceship]].
|-
| data-sort-value="11" | =11 || 8 || p29 reflector || [[Matthias Merzenich]], [[Noam Elkies]], [[David Buckingham]] || [https://conwaylife.com/forums/viewtopic.php?p=8860#p8860]
|- class="expand-child"
| colspan="5" | A [[reflector]] based on a [[Pre-pulsar shuttle 29]] variant.
|-
| data-sort-value="11" | =11 || 8 || [[c/4 diagonal]] [[wickstretcher]] || [[Matthias Merzenich]], [[Jason Summers]], [[Paul Tooke]] || [https://conwaylife.com/forums/viewtopic.php?p=7373#p7373]
|- class="expand-child"
| colspan="5" | A [[fencepost]] for a partial [[c/4 diagonal]] [[wickstretcher]] found by [[Paul Tooke]] in {{year|2004}}.
|-
| 13 || 7 || [[c/5 orthogonal]] [[wickstretcher]] || [[Matthias Merzenich]], [[Hartmut Holzwart]], [[Jason Summers]] || [https://conwaylife.com/forums/viewtopic.php?p=7570#p7570]
|- class="expand-child"
| colspan="5" | The first [[c/5 orthogonal]] [[wickstretcher]] to be found.
|-
| 14 || 5 || [[French kiss]] synthesis || [[Martin Grant]] || [https://conwaylife.com/forums/viewtopic.php?p=9513#p9513]
|- class="expand-child"
| colspan="5" | A 23-glider synthesis for a {{period|3}} oscillator which, despite its size, previously had no known synthesis.
|-
| data-sort-value="15" | =15 || 4 || [https://catagolue.hatsya.com/object/xq4_wp3hz07gg030sxgzgkl0eijggoi12zy61/b3s23/ 41P4H1V0] || [[Jason Summers]] || [https://conwaylife.com/forums/viewtopic.php?p=7780#p7780]
|- class="expand-child"
| colspan="5" | At the time of its discovery, the second smallest known [[c/4 orthogonal]] spaceship.
|-
| data-sort-value="15" | =15 || 4 || [[Period-7 sparkers#Dot sparkers and functional dot sparkers|138P7]] || [[Karel Suhajda]] || [https://conwaylife.com/forums/viewtopic.php?p=8392#p8392]
|- class="expand-child"
| colspan="5" | A fairly strong {{period|7}} [[sparker]], at a time when few were known. It was used to create a {{period|14}} [[traffic light]] [[hassler]].
|}

===2012===
[https://conwaylife.com/forums/viewtopic.php?p=7350#p7350 Entries] ([https://conwaylife.com/forums/viewtopic.php?p=146912#p146912 belated]) • [https://conwaylife.com/forums/viewtopic.php?f=2&t=5747 Voting] • [https://conwaylife.com/forums/viewtopic.php?f=2&t=5747&p=155877&hilit=poty#p155786 Results]

No vote was initially held for {{year|2012}}, but the following patterns were submitted as competition entries by users. User [[137ben]] organized the original competition, while a belated vote was organized by [[atavoidirc]] in 2022 and completed in January 2023.

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Stars
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| 1|| 33 || [[Statorless p3]] || [[Jason Summers]] || [https://conwaylife.com/forums/viewtopic.php?p=6967#p6967]
|- class="expand-child"
| colspan="5" | The first statorless period-3 oscillator.
|-
| 2|| 32|| Direct stable Herschel duplicator || [[Sergey Petrov]] || [https://conwaylife.com/forums/viewtopic.php?p=5915#p5915]
|- class="expand-child"
| colspan="5" | A conduit with a single Herschel input and two independent Herschel outputs.
|-
| =3 || 31|| Period-4 90-degree reflector || [[Karel Suhajda]], [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=7356#p7356]
|- class="expand-child"
| colspan="5" | The first fast period-4 90-degree reflector; works at periods as low as 52.
|-
| =3 || 31|| [[37P4H1V0]] || [[Josh Ball]] || [https://conwaylife.com/forums/viewtopic.php?p=6540#p6540]
|- class="expand-child"
| colspan="5" | A 37-cell c/4 orthogonal spaceship by Josh Ball. In terms of minimum population, it is the smallest known c/4 orthogonal spaceship.
|-
| 5 || 27|| 444-tick [[glider-to-Herschel converter]] || [[Sergey Petrov]] || [https://conwaylife.com/forums/viewtopic.php?p=7102#p7102]
|- class="expand-child"
| colspan="5" | This is the fastest known stable glider-to-Herschel converter/90-degree glider reflector currently known.
|-
| =6|| 26 || Slow two-sided synthesis of the Herschel transmitter || [[Sergey Petrov]] || [https://conwaylife.com/forums/viewtopic.php?t=&p=7261#p7261]
|- class="expand-child"
| colspan="5" | Two-sided syntheses of the standard Herschel transmitter in every orientation where only two gliders interact at any step in the synthesis.
|-
| =6 || 26 || G4 Herschel merge circuit || [[Sergey Petrov]] || [https://conwaylife.com/forums/viewtopic.php?p=5850#p5850] [https://conwaylife.com/forums/viewtopic.php?p=5885#p5885] [https://conwaylife.com/forums/viewtopic.php?p=7200#p7200]
|- class="expand-child"
| colspan="5" | A spartan Herschel transceiver that allows two independent transmitters to feed into the same receiver.
|-
| =8 || 23 || [[HLx111R]] || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=7042#p7042]
|- class="expand-child"
| colspan="5" | A versatile H-to-R conduit that can be used to construct several new Herschel conduits.
|-
| =8 || 23 || New c/5 diagonal rake design || [[Matthias Merzenich]] || [https://github.com/Matthias-Merzenich/jslife-moving/blob/master/velocity-c5d/rake-c5d-p85.rle]
|- class="expand-child"
| colspan="5" | A c/5 diagonal rake design that allows rakes of periods as low as 85.
|-
| =8|| 23 || Herschel-less p62 gun || [[Jason Summers]] || [https://conwaylife.com/forums/viewtopic.php?p=147721#p147721]
|- class="expand-child"
| colspan="5" | The first period-62 glider gun that does not rely on Herschels.
|-
| =11 || 22 || [[86P6H3V0]] || [[ Matthias Merzenich]], [[Josh Ball]] || [https://conwaylife.com/forums/viewtopic.php?p=6222#p6222]
|- class="expand-child"
| colspan="5" | The smallest known 3c/6 orthogonal spaceship.
|-
| =11 || 22 || Low density orphan || [[Marijn Heule]], [[Christiaan Hartman]], [[Kees Kwekkeboom]], [[Alain Noels]] || [https://wwwhomes.uni-bielefeld.de/achim/orphan_8th.html]
|- class="expand-child"
| colspan="5" | An orphan with 92 set cells and only 45 on cells, giving it the lowest density of any known irreducible orphan.
|-
| 13 || 21 || [[Ambidextrous]] G5 [[Herschel transceiver]] || [[Sergey Petrov]], [[Paul Callahan]] || [https://conwaylife.com/forums/viewtopic.php?f=2&t=148&hilit=p504&start=50#p7201] [https://conwaylife.com/forums/viewtopic.php?f=2&t=148&hilit=p504&start=50#p7205]
|- class="expand-child"
| colspan="5" | A spartan Herschel transmitter that can connect to Callahan's spartan Herschel receiver in either of the two possible orientations.
|-
| =14 || 20 || New reflector periods || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=147718#p147718]
|- class="expand-child"
| colspan="5" | The first p26 dependent reflector and p52 and p58 independent reflectors.
|-
| =14 || 20 || New c/4 diagonal spaceships || [[Nicolay Beluchenko]] || [https://conwaylife.com/forums/viewtopic.php?p=147721#p147721]
|- class="expand-child"
| colspan="5" | Large collection of new c/4 diagonal spaceships found with Beluchenko's modification of [[WLS]].
|}

===2011===
[https://conwaylife.com/forums/viewtopic.php?p=4904#p4904 Entries] • [https://conwaylife.com/forums/viewtopic.php?p=5940#p5940 Voting] • [https://conwaylife.com/forums/viewtopic.php?p=6325#p6325 Results]

The following patterns were voted on for the {{year|2011}} competition. Users were able to vote for up to three patterns, but not their own patterns; all votes were weighted equally. [[Adam P. Goucher]] organized the competition.

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Votes
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| data-sort-value="1" | =1 || 10 || [[Fully universal Turing machine]] || [[Paul Rendell]] || [http://rendell-attic.org/gol/fullutm/index.htm]
|- class="expand-child"
| colspan="5" | An extension of the [[Universal Turing machine]] and [[Turing machine]], also by Paul Rendell.
|-
| data-sort-value="1" | =1 || 10 || [[Lobster (spaceship)|Lobster]] || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=4983#p4983]
|- class="expand-child"
| colspan="5" | A c/7 diagonal spaceship found using [[WinLifeSearch]].
|-
| 3 || 7 || [[Garden of Eden 6]] || [[Marijn Heule]], [[Christiaan Hartman]], [[Kees Kwekkeboom]], and [[Alain Noels]] || [http://wwwhomes.uni-bielefeld.de/achim/orphan_7th.html]
|- class="expand-child"
| colspan="5" | A small ({{times|10|10}}), rotationally [[symmetry|symmetric]] [[garden of Eden]] whose [[orphan]] requires only 92 cells to specify.
|-
| data-sort-value="4" | =4 || 6 || Collection of new stable technology || [[Sergey Petrov]] || [https://conwaylife.com/forums/viewtopic.php?p=5234#p5234] [https://conwaylife.com/forums/viewtopic.php?p=5239#p5239]
|-
| data-sort-value="4" | =4 || 6 || Oblique [[antstretcher]] || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=4548#p4548]
|- class="expand-child"
| colspan="5" | An [[antstretcher]] combining a c/5 orthogonal component with a c/4 diagonal component previously found by [[Hartmut Holzwart]] in 2006.
|-
| data-sort-value="6" | =6 || 5 || [[1×N quadratic growth]] || [[Stephen Silver]] || [https://conwaylife.com/forums/viewtopic.php?p=4587#p4587]
|- class="expand-child"
| colspan="5" | The first pattern exhibiting [[quadratic growth]] that starts with the thickness of a single cell, using the [[breeder]] from [[Nick Gotts]]' [[26-cell quadratic growth]].
|-
| data-sort-value="6" | =6 || 5 || [[Pulsar Pixel Display]] || [[Mark Walsh]] || [https://conwaylife.com/forums/viewtopic.php?p=4902#p4902]
|-
| data-sort-value="8" | 8 || 4 || [[Stable]] [[HWSS]] [[Heisenburp]] || [[Sergey Petrov]], [[Richard Schank]], [[Martin Grant]] || [https://conwaylife.com/forums/viewtopic.php?p=5385#p5385]
|-
| 9 || 2 || [[77P6H1V1]] || [[Josh Ball]] || [https://conwaylife.com/forums/viewtopic.php?p=4349#p4349]
|- class="expand-child"
| colspan="5" | The smallest known spaceship of [[c/6 diagonal|this speed]] in terms of its minimum population, found using [[WinLifeSearch]].
|-
| 10 || 1 || Small moving [[sawtooth]] || [[cloudy197]] || [https://conwaylife.com/forums/viewtopic.php?p=5857#p5857]
|}

===2010===
[https://conwaylife.com/forums/viewtopic.php?p=2105#p2105 Entries] • [https://conwaylife.com/forums/viewtopic.php?p=4056#p4056 Voting] • [https://conwaylife.com/forums/viewtopic.php?p=4110#p4110 Results]

The following patterns were voted on for the {{year|2010}} competition. Users were able to vote for up to three patterns, but not their own patterns; all votes were weighted equally. [[Adam P. Goucher]] organized the competition.

{| class="sortable wikitable"
|-
! data-sort-type="number" | Final rank
! data-sort-type="number" | Votes
! Pattern
! Author
! Link(s)
|-
! class="unsortable" colspan="5" | Description
|-
| data-sort-value="1" | 1 || 14 || [[Gemini]] || [[Andrew J. Wade]] || [https://conwaylife.com/forums/viewtopic.php?p=2323#p2323]
|- class="expand-child"
| colspan="5" | The first [[oblique spaceship]] to be constructed, with a speed of (5120,1024)c/33699586.
|-
| data-sort-value="1" | 2 || 9 || [[Phi calculator]] || [[Adam P. Goucher]] || [https://conwaylife.com/forums/viewtopic.php?p=1931#p1931]
|- class="expand-child"
| colspan="5" | A modification of Goucher's similar [[pi calculator]] to instead calculate the digits of the [https://en.wikipedia.org/wiki/Golden_ratio golden ratio].
|-
| data-sort-value="1" | 3 || 6 || [[c/5 diagonal rake]] || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=3761#p3761]
|-
| data-sort-value="1" | =4 || 5 || [[Pianola breeder]]s || [[Paul Tooke]] || [https://conwaylife.com/forums/viewtopic.php?p=3525#p3525]
|- class="expand-child"
| colspan="5" | A series of Gemini-inspired patterns with a growth rate in between [[linear growth|linear]] and [[quadratic growth]].
|-
| data-sort-value="1" | =4 || 5 || [[Merzenich's p31]] || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=3797#p3797]
|- class="expand-child"
| colspan="5" | The first known {{period|31|text=period 31}} oscillator, which also has the ability to reflect gliders 90 degrees.
|-
| data-sort-value="1" | 6 || 4 || Gemini [[gun]]s || [[Dave Greene]] || [https://conwaylife.com/forums/viewtopic.php?p=3036#p3036] [https://web.archive.org/web/20110525070420/http://pentadecathlon.com/lifeNews/2010/07/gemini_guns_1.html]
|-
| data-sort-value="1" | =7 || 2 || [[Sawtooth 260]] || [[David Bell]] || [https://conwaylife.com/forums/viewtopic.php?p=2242#p2242]
|- class="expand-child"
| colspan="5" | Formerly the smallest known [[sawtooth]] in terms of minimum repeating population.
|-
| data-sort-value="1" | =7 || 2 || [[c/5 orthogonal]] [[greyship]]s || [[Hartmut Holzwart]] || [https://conwaylife.com/forums/viewtopic.php?p=2051#p2051]
|-
| data-sort-value="1" | 9 || 1 || [[Period-45 glider gun]] || [[Matthias Merzenich]] || [https://conwaylife.com/forums/viewtopic.php?p=2228#p2228]
|- class="expand-child"
| colspan="5" | The first true-period-45 glider gun to be discovered.
|-
| data-sort-value="1" | =10 || 0 || [[MWSS]] [[Heisenburp]] device || [[Martin Grant]] || [https://conwaylife.com/forums/viewtopic.php?p=2096#p2096]
|-
| data-sort-value="1" | =10 || 0 || [[Beluchenko's other p37]] || [[Nicolay Beluchenko]] || [https://conwaylife.com/forums/viewtopic.php?p=2108#p2108]
|- class="expand-child"
| colspan="5" | The second known {{period|37|text=period 37}} oscillator, and the first one with the ability to reflect gliders 90 degrees.
|-
| data-sort-value="1" | =10 || 0 || [[Flying wing]] [[spaceship]] || [[Emerson J. Perkins]] || [https://conwaylife.com/forums/viewtopic.php?p=2386#p2386]
|- class="expand-child"
| colspan="5" | A [[growing spaceship]] which grows in both dimensions.
|}

==See also==
* [[OCA Discovery of the Year]]

==References==
<references>
<ref name="post2115">{{LinkForumThread
|format = ref
|title = Re: Pattern of the Year 2010 competition
|p = 2115
|author = Adam P. Goucher
|date = April 3, 2010
}}</ref>
<ref name="post27345">{{LinkForumThread
|format = ref
|title = Re: Pattern of the Year 2015 (Votes)
|p = 27345
|author = Alexey Nigin
|date = February 11, 2016
}}</ref>
<ref name="post83979">{{LinkForumThread
|format = ref
|title = Re: 18-bit SL Syntheses (100% Complete!)
|p = 83979
|author = Ian07
|date = October 9, 2019
}}</ref>
</references>

[[Category:Everything else]]
[[Category:Competitions]]

__NOTOC__

Template:LinkYouTube

2024-04-21T07:12:10Z

Apple Bottom: Spacing fix (I hope)

<includeonly>{{#ifeq: {{{id|}}} | | '''Error: id= parameter not specified!''' [[Category:Pages that link to YouTube videos with missing IDs]] | {{#ifeq: {{{title|}}} | | {{#ifeq: {{{author|}}} | | | {{{author}}}:  }}[https://www.youtube.com/watch?v={{{id}}} YouTube video {{{id}}}] [[Category:Pages that link to YouTube videos with missing titles]] | {{#ifeq: {{{author|}}} | | | {{{author}}}:  }}[https://www.youtube.com/watch?v={{{id}}} {{{title}}}] }} (YouTube video) [[Category:Pages that link to YouTube]] }}</includeonly><noinclude>This is a template for including links to YouTube videos in the "External Links" section of an article. It can take the following parameters:

* ''id'', the id number of the video being linked to (mandatory);
* ''title'', the title of the video being linked to (optional but recommended);
* ''author'', the name of the author (creator) of the video (optional).

Here are some simple usage examples:

'''You type:'''

<tt><nowiki>{{LinkYoutube|id=eZ9BBcskBjY|title=Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period}}</nowiki></tt>

'''You see:'''

[https://www.youtube.com/watch?v=eZ9BBcskBjY Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period] (YouTube video)

'''You type:'''

<tt><nowiki>{{LinkYoutube|id=eZ9BBcskBjY|author=[[Nathaniel Johnston]]|title=Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period}}</nowiki></tt>

'''You see:'''

[[Nathaniel Johnston]]: [https://www.youtube.com/watch?v=eZ9BBcskBjY Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period] (YouTube video)

'''You type:'''

<tt><nowiki>{{LinkYoutube|id=eZ9BBcskBjY}}</nowiki></tt>

'''You see:'''

[https://www.youtube.com/watch?v=eZ9BBcskBjY YouTube video eZ9BBcskBjY] (YouTube video)

'''You type:'''

<tt><nowiki>{{LinkYoutube|title=Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period}}</nowiki></tt>

'''You see:'''

'''Error: id= parameter not specified!'''

==See also==

{{ListOfLinkTemplates}}
[[Category:Citation templates]]
</noinclude>

Template:LinkYouTube

2024-04-21T07:10:50Z

Apple Bottom: Add author= parameter

<includeonly>{{#ifeq: {{{id|}}} | | '''Error: id= parameter not specified!''' [[Category:Pages that link to YouTube videos with missing IDs]] | {{#ifeq: {{{title|}}} | | {{#ifeq: {{{author|}}} | | | {{{author}}}: }}[https://www.youtube.com/watch?v={{{id}}} YouTube video {{{id}}}] [[Category:Pages that link to YouTube videos with missing titles]] | {{#ifeq: {{{author|}}} | | | {{{author}}}: }}[https://www.youtube.com/watch?v={{{id}}} {{{title}}}] }} (YouTube video) [[Category:Pages that link to YouTube]] }}</includeonly><noinclude>This is a template for including links to YouTube videos in the "External Links" section of an article. It can take the following parameters:

* ''id'', the id number of the video being linked to (mandatory);
* ''title'', the title of the video being linked to (optional but recommended);
* ''author'', the name of the author (creator) of the video (optional).

Here are some simple usage examples:

'''You type:'''

<tt><nowiki>{{LinkYoutube|id=eZ9BBcskBjY|title=Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period}}</nowiki></tt>

'''You see:'''

[https://www.youtube.com/watch?v=eZ9BBcskBjY Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period] (YouTube video)

'''You type:'''

<tt><nowiki>{{LinkYoutube|id=eZ9BBcskBjY|author=[[Nathaniel Johnston]]|title=Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period}}</nowiki></tt>

'''You see:'''

[[Nathaniel Johnston]]: [https://www.youtube.com/watch?v=eZ9BBcskBjY Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period] (YouTube video)

'''You type:'''

<tt><nowiki>{{LinkYoutube|id=eZ9BBcskBjY}}</nowiki></tt>

'''You see:'''

[https://www.youtube.com/watch?v=eZ9BBcskBjY YouTube video eZ9BBcskBjY] (YouTube video)

'''You type:'''

<tt><nowiki>{{LinkYoutube|title=Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period}}</nowiki></tt>

'''You see:'''

'''Error: id= parameter not specified!'''

==See also==

{{ListOfLinkTemplates}}
[[Category:Citation templates]]
</noinclude>

Nathaniel Johnston

2024-04-20T09:35:00Z

Apple Bottom: Link to YouTube channel; put personal home page first in external links

{{Person|name=Nathaniel Johnston|res=Canada|image=true|born=January 1985|inst=Mount Allison University, Sackville, New Brunswick, Canada|alma=University of Guelph, Guelph, Ontario, Canada}}
{{For|Nathaniel Johnston's userpage|User:Nathaniel}}
'''Nathaniel Johnston''' is a [[Life enthusiast]], founder and head administrator of [[LifeWiki]].

He is Associate Professor in the Department of Mathematics and Computer Science at Mount Allison University, Sackville, New Brunswick, Canada. With [[Dave Greene]], he co-authored [[Conway's Game of Life: Mathematics and Construction]].

{{PatternsFoundBy|name=Nathaniel Johnston}}

{{DEFAULTSORT:Johnston, Nathaniel}}

==External links==
*[http://www.njohnston.ca/ Nathaniel Johnston's home page]
*[https://www.youtube.com/@NathanielMath Nathaniel Johnston's YouTube channel]
*[https://mta.ca/directory/nathaniel-johnston Mount Allison University Directory: Nathaniel Johnston]
*{{MathGenealogy|id=186633|title=Nathaniel Johnston}}

Category:Pages that link to YouTube videos with missing titles

2024-04-19T17:04:27Z

Apple Bottom: Created page with "This category tracks all pages that use the {{tl|LinkYouTube}} template but do not specify the title of the linked video. Category:Pages needing attention __HIDDENCAT__"

This category tracks all pages that use the {{tl|LinkYouTube}} template but do not specify the title of the linked video.

[[Category:Pages needing attention]]
__HIDDENCAT__

Category:Pages that link to YouTube videos with missing IDs

2024-04-19T17:04:16Z

Apple Bottom: Created page with "This category tracks all pages that use the {{tl|LinkYouTube}} template but do not specify a video ID to link to. Category:Pages needing attention __HIDDENCAT__"

This category tracks all pages that use the {{tl|LinkYouTube}} template but do not specify a video ID to link to.

[[Category:Pages needing attention]]
__HIDDENCAT__

Category:Pages that link to YouTube

2024-04-19T17:03:05Z

Apple Bottom: Created page with "{{CategoryTools}} This maintenance category contains pages that link to YouTube via the {{tl|LinkYouTube}} template. YouTube __HIDDENCAT__"

{{CategoryTools}}
This maintenance category contains pages that link to YouTube via the {{tl|LinkYouTube}} template.

[[Category:Pages that link to external sites|YouTube]]
__HIDDENCAT__

Herschel circuit

2024-04-19T17:01:41Z

Apple Bottom: Link to Nathaniel's first video on Herschel tracks

{{Glossary}}
A '''Herschel circuit''' or '''Herschel track''' is a series of [[Herschel conduit]]s or other components, connected by placing them so that the output [[Herschel]]s from early [[conduit]]s become the input Herschels for later conduits. Often the initial component is a [[converter]] accepting some other signal type as input -- usually a [[glider]], in which case either a [[syringe]] or [[bronco]] is most commonly used. The [[Silver reflector]] is a well-known early [[Spartan]] Herschel circuit from before the syringe was discovered, where the initial converter is a [[Callahan G-to-H]].

Sometimes a direct connection between two conduits is not possible due to unwanted gliders that destroy required [[catalyst]]s, or wanted gliders that are not able to escape. In this case, small "spacer" conduits such as [[F116]], [[F117]], [[Fx77]], [[R64]], [[L112]], or [[L156]] can be inserted between the other conduits to solve the problem.

Some converter or [[factory]] conduits do not produce a Herschel as output, instead generating other useful results such as gliders, [[boat]]s or [[MWSS]]es; see [[Herschel-to-glider]], [[demultiplexer]], and [[H-to-MWSS]] respectively for examples of these. For those conduits which do produce an unwanted Herschel, an [[eater]] such as [[SW-2]] can be added to delete it.

If the first and last conduits of a chain connect to each other in a loop then there is no need for a G-to-H to generate the first Herschel, or an eater to consume the last one. The circuit becomes a self-supporting [[Herschel loop]]. A loop is also formed by a G-to-H connected to a Herschel-to-glider converter, with the glider reflected back to the G-to-H's input with glider reflectors of the appropriate [[colour]], usually [[Snark]]s. In either case, if the loop has a surplus glider output, it becomes a [[gun]]; if no output is available it is an [[emu]].

==External links==
* {{LinkLexicon|lex_h.htm#herschelcircuit}}
* {{LinkForumThread|format=ref|f=2|t=144|title=Herschel conduits and other stable circuits}}
* {{LinkForumThread|format=ref|f=2|t=148|title=Finally trying out stable Herschel tracks...}}
* Videos by [[Nathaniel Johnston]] on Herschel tracks:
** {{LinkYouTube|id=eZ9BBcskBjY|title=Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period}}

Template:LinkYouTube

2024-04-19T17:01:23Z

Apple Bottom:

<includeonly>{{#ifeq: {{{id|}}} | | '''Error: id= parameter not specified!''' [[Category:Pages that link to YouTube videos with missing IDs]] | {{#ifeq: {{{title|}}} | | [https://www.youtube.com/watch?v={{{id}}} YouTube video {{{id}}}] [[Category:Pages that link to YouTube videos with missing titles]] | [https://www.youtube.com/watch?v={{{id}}} {{{title}}}] }} (YouTube video) [[Category:Pages that link to YouTube]] }}</includeonly><noinclude>This is a template for including links to YouTube videos in the "External Links" section of an article. It can take the following parameters:

* ''id'', the id number of the video being linked to (mandatory);
* ''title'', the title of the video being linked to (optional but recommended).

Here are three simple usage examples:

'''You type:'''

<tt><nowiki>{{LinkYoutube|id=eZ9BBcskBjY|title=Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period}}</nowiki></tt>

'''You see:'''

[https://www.youtube.com/watch?v=eZ9BBcskBjY Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period] (YouTube video)

'''You type:'''

<tt><nowiki>{{LinkYoutube|id=eZ9BBcskBjY}}</nowiki></tt>

'''You see:'''

[https://www.youtube.com/watch?v=eZ9BBcskBjY YouTube video eZ9BBcskBjY] (YouTube video)

'''You type:'''

<tt><nowiki>{{LinkYoutube|title=Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period}}</nowiki></tt>

'''You see:'''

'''Error: id= parameter not specified!'''

==See also==

{{ListOfLinkTemplates}}
[[Category:Citation templates]]
</noinclude>

Template:LinkYoutube

2024-04-19T17:00:54Z

Apple Bottom: Redirected page to Template:LinkYouTube

#REDIRECT [[Template:LinkYouTube]]

Template:LinkYouTube

2024-04-19T17:00:41Z

Apple Bottom: Created page with "<includeonly>{{#ifeq: {{{id|}}} | '''Error: id= parameter not specified!''' Category:Pages that link to YouTube videos with missing IDs | {{#ifeq: {{{title|}}} | [https://www.youtube.com/watch?v={{{id}}} YouTube video {{{id}}}] Category:Pages that link to YouTube videos with missing titles | [https://www.youtube.com/watch?v={{{id}}} {{{title}}}] }} (YouTube video) Category:Pages that link to YouTube }}</includeonly><noinclude>T..."

<includeonly>{{#ifeq: {{{id|}}} | '''Error: id= parameter not specified!''' [[Category:Pages that link to YouTube videos with missing IDs]] | {{#ifeq: {{{title|}}} | [https://www.youtube.com/watch?v={{{id}}} YouTube video {{{id}}}] [[Category:Pages that link to YouTube videos with missing titles]] | [https://www.youtube.com/watch?v={{{id}}} {{{title}}}] }} (YouTube video) [[Category:Pages that link to YouTube]] }}</includeonly><noinclude>This is a template for including links to YouTube videos in the "External Links" section of an article. It can take the following parameters:

* ''id'', the id number of the video being linked to (mandatory);
* ''title'', the title of the video being linked to (optional but recommended).

Here are three simple usage examples:

'''You type:'''

<tt><nowiki>{{LinkYoutube|id=eZ9BBcskBjY|title=Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period}}</nowiki></tt>

'''You see:'''

[https://www.youtube.com/watch?v=eZ9BBcskBjY Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period] (YouTube video)

'''You type:'''

<tt><nowiki>{{LinkYoutube|id=eZ9BBcskBjY}}</nowiki></tt>

'''You see:'''

[https://www.youtube.com/watch?v=eZ9BBcskBjY YouTube video eZ9BBcskBjY] (YouTube video)

'''You type:'''

<tt><nowiki>{{LinkYoutube|title=Herschel tracks in Conway's Game of Life - Part 1 - Making oscillators of any large period}}</nowiki></tt>

'''You see:'''

'''Error: id= parameter not specified!'''

==See also==

{{ListOfLinkTemplates}}
[[Category:Citation templates]]
</noinclude>

User talk:Apple Bottom

2024-03-28T07:29:15Z

Apple Bottom:

Hey, you are back!

:Hey! Not actually; I really just popped back in randomly look at the front page and the new discoveries and developments. Ended up making an edit or two, but that's the extent of it. I'm still alive, yes; but I don't have time anymore to devote to such things as Life (as opposed to life).

:That said it sure is nice that somebody not only noticed, but cared enough to say hi again. Thanks! [[User:Apple Bottom|Apple Bottom]] ([[User talk:Apple Bottom|talk]]) 19:40, 11 October 2023 (UTC)

:: I'm sure that lots more than one person will notice. Welcome back temporarily, and please drop by again any time! [[User:Dvgrn|Dvgrn]] ([[User talk:Dvgrn|talk]]) 00:23, 12 October 2023 (UTC)

:::Thanks! That's very nice to hear, I appreciate the kind words. (Still not back BTW, just popping in again very briefly.) [[User:Apple Bottom|Apple Bottom]] ([[User talk:Apple Bottom|talk]]) 07:29, 28 March 2024 (UTC)

Heavy

2024-03-28T07:28:57Z

Apple Bottom: New glossary

A 2 × 2 square of [[cell]]s in a [[pattern]] is said to be '''heavy''' if, at any time during the evolution of the pattern, at least three of its four cells are alive in the same [[generation]].<ref>[[Adam P. Goucher]], ''[https://cp4space.hatsya.com/2024/01/20/every-finite-phoenix-has-period-2/ Every finite phoenix has period 2]'', January 20 2024</ref>

==References==
<references />

{{Glossary}}

Superluminous

2023-10-11T19:53:56Z

Apple Bottom: See talk page

{{Glossary}}
A [[speed]] is said to be '''superluminous''' if it exceeds the [[speed of light]], ''c''. Just as in real life, information cannot be transmitted faster than the speed of light in [[Conway's Game of Life]] and [[Life-like cellular automaton|similar CAs]]; there are, however, patterns that give the illusion of this happening, with the [[Fast Forward Force Field]] (shown below) and the [[star gate]] built on it being prominent examples.

{{EmbedViewer
|pname = fastforwardforcefield
|viewerconfig = #C [[ HEIGHT 360 WIDTH 600 THUMBSIZE 2 ZOOM 28 ]]
|position = center
|caption = The Fast Forward Force Field
|style = width:300px;
}}

In more general classes of [[cellular automaton|cellular automata]], greater care must be taken when discussing the speed of light. If ''c'' is defined as the maximum speed at which any effect can propagate, then superluminosity is impossible by definition. If, on the other hand, ''c'' is defined as a speed of one [[cell]] per [[tick]], then effects can propagate at superluminous speed, and information transmitted faster than the speed of light. [[Larger than Life]] rules are an example of a class of CAs where this distinction is important.

Talk:Superluminous

2023-10-11T19:49:59Z

Apple Bottom: Created page with "==Superluminosity in LtL rules== A quick note: the statement about LtL rules is at odds with the definition of the speed of light given on the speed page ("the fastest possible speed at which any effect can propagate"). Using that definition, in LtL rules, c is a speed that's greater than one cell per tick (and the statement given here incorrect). That said, it's probably deeply ingrained in both people's minds and the notation we use that (e.g. to write down spacesh..."

==Superluminosity in LtL rules==
A quick note: the statement about LtL rules is at odds with the definition of the speed of light given on the [[speed]] page ("the fastest possible speed at which any effect can propagate"). Using that definition, in LtL rules, c is a speed that's greater than one cell per tick (and the statement given here incorrect). That said, it's probably deeply ingrained in both people's minds and the notation we use that (e.g. to write down spaceship speeds) that "c" does in fact mean "one cell per tick", in which case the statement given here is correct.

I vaguely remember unpleasant heated discussions about which definition of the speed of light is proper that I don't want to revisit. But I would suggest that these two different concepts, namely the maximum speed at which effects can propagate, and the speed of one cell per tick, just so ''happen'' to coincide for Life and many other CAs, that they must be distinguished in general, and this should be clarified. I'll go and make the edit here; if there's disagreement, please edit and improve this page further. I'll not make changes to the [[speed]] page, someone else can do that. [[User:Apple Bottom|Apple Bottom]] ([[User talk:Apple Bottom|talk]]) 19:49, 11 October 2023 (UTC)

User talk:Apple Bottom

2023-10-11T19:40:03Z

Apple Bottom:

Apgcode

2023-10-08T10:57:51Z

Apple Bottom: /* Encoding objects */

An '''apgcode''' is a unique identifier used by [[apgsearch]] and its search results database, [[Catagolue]], to classify and denote a [[pattern]]. A pattern's name may also be its apgcode (especially for small, otherwise unnamed patterns).

== Encoding objects ==
An apgcode consists of a prefix and a suffix, separated by an underscore. Both the prefix and the suffix are alphanumeric strings.

=== Prefix ===
The prefix consists of a two-character type and a number. For encodable objects, the types are:

* <tt>xs</tt> for a [[still life]];
* <tt>xp</tt> for an [[oscillator]];
* <tt>xq</tt> for a [[spaceship]];
* <tt>yl</tt> for a periodic linearly growing object, such as a [[puffer]] or [[gun]];
* <tt>methuselah</tt> for a [[methuselah]];
* <tt>messless</tt> for a [[diehard]]; and
* <tt>megasized</tt> for a soup with a large final population.

The number following the type represents the [[population]] for a still life, the lifespan for a methuselah or diehard, or otherwise the [[period]] of the object.
For a example, see [[xp2]].

Note that despite always having a constant shape and population, spaceships of period 1 are classified under <tt>xq</tt> rather than under <tt>xs</tt> or a dedicated period-1 spaceship prefix.

=== Suffix ===
In codes for <tt>xs</tt>, <tt>xp</tt>, and <tt>xq</tt>, the suffix following the underscore is a representation of the object in Extended Wechsler Format (see below).

In codes for <tt>yl</tt>, the suffix consists of additional information encoding higher-order periods of the pattern:<ref>https://conwaylife.com/forums/viewtopic.php?p=71429#p71429</ref>

* The first value is a number representing the "population growth" of the pattern, which is related to (but not necessarily identical to) the period. For example:
** Despite the [[block-laying switch engine]] having a period of 288, its value is 144 due to [[glide symmetry]].
** Likewise, a diagonal puffer from [[HighLife]] has a value of 960 rather than the expected 192 due to creating period-10 oscillators out of phase with each other.
* The second value represents the period at which the population of the debris fluctuates.
* The third value represents how much the population grows after the amount of generations specified in the first value have elapsed.
* What the fourth value corresponds to is currently not known; it appears to be a hashing function.

=== Unencodable objects ===
In their original form, apgcodes are not guaranteed to encode still lifes, oscillators and spaceships exceeding a 40×40 bounding box.{{refn|group=note|Patterns exceeding a 40×40 bounding box can still be encoded using "classic" apgcodes if they match either fit within such a box in at least one phase, or if, alternatively, they do not contain runs of more than 39 zeroes in their extended Wechsler representation.}} These are instead reported by apgsearch and censused by Catagolue as ''oversized'' patterns, using the following types:

* <tt>ov_s</tt> for an oversized still life;
* <tt>ov_p</tt> for an oversized oscillator;
* <tt>ov_q</tt> for an oversized spaceship.

These types are then followed by a number representing the population for a still life, or otherwise the period of the object, as in the non-oversized case. apgcodes of this form do not uniquely identify a specific object, but rather represent classes of objects.

An extension to apgcodes, dubbed "greedy apgcodes" (see below), was later used to relax the 40×40 bounding box constraint, although some sufficiently large patterns remain canonically unencodable.

=== Unclassifiable objects ===
Objects which apgsearch cannot classify as above are denoted by one of:

* <tt>zz_EXPLOSIVE</tt>
* <tt>zz_LINEAR</tt>
* <tt>zz_QUADRATIC</tt>
* <tt>zz_REPLICATOR</tt>
* <tt>PATHOLOGICAL</tt> (e.g. high-period oscillators)

Chaotic-growth (<tt>zz_*</tt>) patterns are classified according to certain heuristics; the labels chosen do not necessarily reflect the nature of the object encountered, so an object classified as e.g. <tt>zz_REPLICATOR</tt> need not be an actual [[replicator]].

Like oversized apgcodes, these apgcodes do not uniquely identify specific objects.

== Extended Wechsler format ==
Non-oversized still lifes, oscillators and patterns are encoded in '''extended Wechsler format''', an extension of a pattern notation developed by [[Allan Wechsler]] in 1992.

* The pattern is separated into horizontal strips of five rows.
** Each strip, ''n'' columns wide, is encoded as a string of ''n'' characters in the set {<tt>0</tt>, <tt>1</tt>, <tt>2</tt>, ..., <tt>8</tt>, <tt>9</tt>, <tt>a</tt>, <tt>b</tt>, ..., <tt>v</tt>} denoting the five cells in a vertical column corresponding to the bitstrings {'00000', '00001', '00010', ..., '01000', '01001', '01010', '01011', ... '11111'}.
** The characters '<tt>w</tt>' and '<tt>x</tt>' are used to abbreviate '<tt>00</tt>' and '<tt>000</tt>', respectively, and the symbols {'<tt>y0</tt>', '<tt>y1</tt>', <tt>y2</tt>', ..., '<tt>yx</tt>', '<tt>yy</tt>', '<tt>yz</tt>'} are used to encode runs of between 4 and 39 consecutive '<tt>0</tt>'s.
** Extraneous '<tt>0</tt>'s at the ends of strips are not included in the encoding. (Note that in particular, blank five-row strips are represented by the empty string.)
* The character '<tt>z</tt>' separates contiguous five-row strips.

=== Examples ===
<tt>xq4_27deee6</tt> encodes a [[heavyweight spaceship]]:

[[File:xq4 27deee6 annotated.png|center]]

<tt>xs31_0ca178b96z69d1d96</tt> encodes a 31-bit still life; note how the '<tt>z</tt>' separates the two five-row strips:

{| style="margin-left: auto; margin-right: auto;"
|-
| style="padding-bottom: 0.5em;" | [[File:xs31 0ca178b96z69d1d96 annotated strip1.png|center]]
|-
| style="padding-bottom: 0.5em;" | [[File:xs31 0ca178b96z69d1d96 annotated strip2.png]]
|}

<tt>xp30_w33z8kqrqk8zzzx33</tt> encodes a [[trans-queen bee shuttle]]; note how five-row strips are represented by the empty string:

{| style="margin-left: auto; margin-right: auto;"
|-
| style="padding-bottom: 0.5em;" | [[File:Xp30 w33z8kqrqk8zzzx33 annotated strip1.png|center]]
|-
| style="padding-bottom: 0.5em;" | [[File:Xp30 w33z8kqrqk8zzzx33 annotated strip2.png|center]]
|-
| style="padding-bottom: 0.5em;" | <center>(10 blank rows omitted)</center>
|-
| [[File:Xp30 w33z8kqrqk8zzzx33 annotated striplast.png|center]]
|}

<tt>xp2_31a08zy0123cko</tt> is a [[quadpole tie ship]]; note how trailing zeros in the first five-row strip are not encoded:

{| style="margin-left: auto; margin-right: auto;"
|-
| style="padding-bottom: 0.5em;"| [[File:xp2 31a08zy0123cko annotated strip1.png|center]]
|-
| [[File:xp2 31a08zy0123cko annotated strip2.png|center]]
|}

== Canonical form ==
In order to enforce a canonical form, there are further rules regarding encoding:

* The leftmost column and uppermost row must each contain at least one live cell. (This gives a canonical position.)
* A canonical orientation and phase must be determined. For example, with the [[caterer]] (p3 oscillator with no [[symmetry]]), there are three phases and eight orientations, so we have 24 possible encodings. A total order on these encodings is defined as follows:
** Shorter representations are preferred to longer representations;
** For representations of the same length, lexicographical ASCII ordering is applied, and preference given to earlier strings.

This gives, for any still-life, oscillator or spaceship, an unambiguous canonical code to represent the pattern. It has several desirable properties:

* Compression: it is much more compact than [[RLE]] or [[SOF]] for storing very small patterns, and sometimes even beats the common name ('<tt>xp15_4r4z4r4</tt>' is shorter than '[[pentadecathlon]]')!
* Character set: it only uses digits, lowercase letters and the underscore, so can be safely used in filenames and URLs.
* Human-readability: the prefix means that we can instantly see whether a particular object is a still-life (and if so, what size), oscillator (and if so, what period) or spaceship (and if so, what period). It also means that the string is instantly recognised as being an encoding of an object ('<tt>xp2_7</tt>' is obviously a [[blinker]], whereas the digit 7 on its own with no extra context is ambiguous).

== Adapting apgcodes to larger patterns ==
As apgcodes were originally limited to patterns fitting into a 40×40 bounding box, different ways of extending them to allow unambiguously encoding larger patterns were proposed.<ref name="forumthread2307" /> In their original form, apgcodes are not guaranteed to be able to encode larger patterns, due a lack of well-definedness for runs of 40 or more consecutive zeroes, and apgsearch versions up to 3.x would report such patterns as oversized instead of attempting to encode them.

Extended ("greedy") apgcodes were eventually adopted to allow larger patterns to be encoded. These avoid the problem by stipulating that a run of ''n'' zeroes be encoded as follows:

# If ''n'' is less than 40, the run is encoded as in regular apgcodes, using the characters <tt>w</tt>, <tt>x</tt>, and <tt>y0</tt> .. <tt>yz</tt> as appropriate.
# If ''n'' is equal to or greater than 40, the run is encoded as <tt>yz</tt> (representing the first 39 zeroes), following by the encoding for a run of ''n'' - 39 zeroes according to this definition.

That is to say:

:[[File:Extended apgcodes zeroes encoding.png]]

This extension, which is used on the LifeWiki for larger patterns, retains compatibility with existing apgcode decoders. Adapting encoders to produce extended apgcodes is similarly straightforward.

Greedy apgcodes were adopted for [[apgsearch]] 4.x<ref name="post48682" />, subject to the following constraints:

* (width + 2) * (height + 2) <= 10000;
* the resulting apgcode, without the prefix, cannot exceed 1280 bytes.

== Adapting apgcodes to multistate rules ==
Work is ongoing on extending apgcodes to multistate ([[Generations]]) rules.<ref name="post47999" /> For this, apgcodes encoding still lifes, oscillators and spaceships will contain multiple suffixes, separated by underscores.{{refn|group=note|That is to say, these apgcodes will match the following regular expression: <tt>x[spq][0-9]+(_[0-9a-z]+)*</tt>}}

Each suffix will encode one 'layer' of the pattern, with patterns in an ''n''-state rule having 2+&lceil;log2(''n''-2)&rceil; layers, where layer 0 is 'live', layer 1 is 'refractory', and the remaining layers implement a binary counter.

More precisely, a pattern in an ''n''-state [[Generations]] rule is represented as follows:<ref name="post49788" /><ref name="post49793" />

# "Dying" states are renumbered to 2, 6, 10, 14, 18, ..., in reverse chronological order.
# Each state is represented as a binary number.
# An extended Wechsler representation is generated for each bit position, starting with the least significant bit.
# The resulting representations, now called "layers" are concatenated with underscores to form a representation of the entire pattern.

To obtain the pattern's canonical object, representations are generated for each phase and each possible orientation of the pattern, and the canonical representation is chosen as described in the "Canonical form" section above. Finally, a suitable prefix describing the pattern's overall behavior is prepended.

In 3-state rules, this simplifies to the two layers directly representing cell states 1 and 2, respectively.

=== Examples ===
For example, the following spaceship in [[Brian's Brain]] ([[Generations]] rule /2/3, aka B2/S/G3) is represented by the apgcode <tt>xq4_3482h8a_03482lx8</tt>:

{{EmbedViewer
|apgcode = xq4_3482h8a_03482lx8/g3b2s
|position = center
|viewerconfig = [[ GRID GRIDMAJOR 0 GPS 2 AUTOSTART THUMBLAUNCH THUMBSIZE 2 TRACKLOOP 4 -1 0 COLOR 2 128 128 128 ]]
|rle =
x = 11, y = 5, rule = /2/3
AB2.AB$AB.AB$.AB.A4.B$2.AB4.A.B$4.AB2.B!
}}

As [[Brian's Brain]] is a 3-state rule, the two layers of the code directly represent cells in states 1 (live) and 2 (dying); note how <tt>x</tt> represents <tt>000</tt> in the second layer:

{| style="margin-left: auto; margin-right: auto;"
|-
| style="padding-bottom: 0.5em; padding-right: 0.5em" | [[File:xq4 3482h8a 03482lx8 layer1 annotated.png]]
| style="padding-bottom: 0.5em; padding-left: 0.5em" | [[File:xq4 3482h8a 03482lx8 layer2 annotated.png]]
|}

Putting both layers together yields the complete pattern:

{| style="margin-left: auto; margin-right: auto;"
|-
| style="padding-bottom: 0.5em;" | [[File:xq4 3482h8a 03482lx8 annotated.png]]
|}

For a more complex example, consider the following [[reflectorless rotating oscillator]] in an 11-state [[Generations]] version of [[Conway's Game of Life]] (23/3/11), <tt>xp32_ss2gzw11_wsfm76cg_x86668_wke2024_ws6i1_x1</tt>:

{{EmbedViewer
|apgcode = xp32_ss2gzw11_wsfm76cg_x86668_wke2024_ws6i1_x1/g11b3s23
|position = center
|viewerconfig = [[ GRID GRIDMAJOR 0 GPS 16 AUTOSTART THUMBLAUNCH THUMBSIZE 2 LOOP 32 WIDTH 640 HEIGHT 640 ZOOM 32 ]]
|rle =
x = 9, y = 6, rule = 23/3/11
3.B.F$2.ADCIG$2A2D3IH$2AFG3.I$2ADAF3.J$2.2A!
}}

In order to encode this pattern, states 2, 3, ..., 10 are renumbered 34, 30, ..., 6, 2; six layers are then used to encode each bit of these new state numbers:

{| style="margin-left: auto; margin-right: auto;"
|-
| style="padding-bottom: 0.5em; padding-right: 0.5em" | [[File:xp32 ss2gzw11 wsfm76cg x86668 wke2024 ws6i1 x1 layer1 annotated.png]]
| style="padding-bottom: 0.5em; padding-left: 0.5em; padding-right: 0.5em" | [[File:xp32 ss2gzw11 wsfm76cg x86668 wke2024 ws6i1 x1 layer2 annotated.png]]
| style="padding-bottom: 0.5em; padding-left: 0.5em; padding-right: 0.5em" | [[File:xp32 ss2gzw11 wsfm76cg x86668 wke2024 ws6i1 x1 layer3 annotated.png]]
| style="padding-bottom: 0.5em; padding-left: 0.5em; padding-right: 0.5em" | [[File:xp32 ss2gzw11 wsfm76cg x86668 wke2024 ws6i1 x1 layer4 annotated.png]]
| style="padding-bottom: 0.5em; padding-left: 0.5em; padding-right: 0.5em" | [[File:xp32 ss2gzw11 wsfm76cg x86668 wke2024 ws6i1 x1 layer5 annotated.png]]
| style="padding-bottom: 0.5em; padding-left: 0.5em;" | [[File:xp32 ss2gzw11 wsfm76cg x86668 wke2024 ws6i1 x1 layer6 annotated.png]]
|}

Putting the layers together yields the complete pattern:

{| style="margin-left: auto; margin-right: auto;"
|-
| style="padding-bottom: 0.5em;" | [[File:xp32 ss2gzw11 wsfm76cg x86668 wke2024 ws6i1 x1 annotated.png]]
|}

== Long-lived soups ==
Unlike with other patterns, apgcodes for [[methuselah]]s and [[diehard]]s classify the soup itself rather than the individual objects that emerge from it, and do not convey any information other than the soup's lifespan.

Ordinary methuselahs are classified under the <tt>methuselah</tt> prefix with the suffix being the soup's lifespan with the last three digits truncated and the letter <tt>k</tt> to stand for "thousand." For example, [[42100M]] was recorded by [[apgsearch]] as <tt>methuselah_42k</tt>, and is therefore collected by [[Catagolue]] with all other soups lasting between 42,000 and 42,999 generations.{{refn|group=note|Only methuselahs lasting at least 25,000 generations are reported by apgsearch, and only by versions v4.54 or later. Additionally, apgsearch estimates the lifespan of each soup before testing it more precisely, and is not guaranteed to detect all <tt>methuselah_25k</tt> soups.}}

Diehards, or long-lived soups which leave behind no [[ash]], are classified similar to other methuselahs, but under the <tt>messless</tt> prefix. Only two digits are truncated for messless soups and replaced with the letter <tt>h</tt> to stand for "hundred."{{refn|group=note|Only diehards lasting at least 500 generations are reported by apgsearch, and only by versions v4.69 or later.}}

Soups with large final populations are classified under the <tt>megasized</tt> prefix. Like with diehards, two digits are truncated from the population count.{{refn|group=note|Only soups with final populations of at least 3,000 are reported by apgsearch, and only by versions v5.03 or later.}}

== Limitations ==
An apgcode does not encode the rule with the pattern. An apgcode can be ambiguous if a rule is neither specified nor implicitly assumed, with the same code being assigned to different patterns evolving differently. For example, the code <tt>xp2_2a54</tt> describes at least three different period-2 oscillators in outer-totalistic rules which are all titled as "[[clock]]"; further variants exist in [[non-totalistic cellular automaton|non-totalistic rules]]:

{| style="margin-left: auto; margin-right: auto;" class="wikitable"
|+ Evolution of xp2_2a54 across different rules
|-
| align="center" | [[File:Xp2 2a54 b3s23.gif]]
| align="center" | [[File:Xp2 2a54 b34s.gif]]
| align="center" | [[File:Xp2 2a54 b4s1.gif]]
|-
| B3/S3 to B35678/S02345678
| B34/S to B345678/S0245678
| B4/S1 to B45678/S01245678
|}

Apgcode was not designed to encode arbitrary patterns in an unambiguous way (including infinite growth patterns and active regions).<ref>{{LinkForumThread|p=132285|title=Re: Thread for basic questions|format=ref}}</ref> The exact location and orientation of a pattern and the specific phase of a periodic pattern are not encoded in an apgcode.<ref>{{LinkForumThread|p=132288|title=Re: Thread for basic questions|format=ref}}</ref>

== See also ==
* [[Catagolue naming conventions]]
* [[File formats]]

== Notes ==
<references group="note" />

== References ==
<references>
<ref name="forumthread2307">{{LinkForumThread
|f = 7
|t = 2307
|title = Extending apgcodes to larger patterns
|format = ref
|author = Apple Bottom
|date = July 25, 2016
}}</ref>
<ref name="post47999">{{LinkForumThread
|p = 47999
|title = Re: apgsearch v3.1
|format = ref
|author = Adam P. Goucher
|date = August 4, 2017
}}</ref>
<ref name="post48682">{{LinkForumThread
|p = 48682
|title = Re: Extending apgcodes to larger patterns
|format = ref
|author = Adam P. Goucher
|date = August 12, 2017
}}</ref>
<ref name="post49788">{{LinkForumThread
|p = 49788
|title = Re: Catagolue browser extension
|format = ref
|author = BlinkerSpawn
|date = August 24, 2017
}}</ref>
<ref name="post49793">{{LinkForumThread
|p = 49793
|title = Re: Catagolue browser extension
|format = ref
|author = Adam P. Goucher
|date = August 24, 2017
}}</ref>
</references>

{{CatagolueNavbox}}

[[Category:Everything else]]
[[Category:File formats]]
[[Category:Algorithms]]

{{DISPLAYTITLE:apgcode}}

Star gate

2023-10-08T10:37:06Z

Apple Bottom:

{{Oscillator
|name = Star gate
|pname = stargate
|c = 1099
|bx = 155
|by = 126
|p = 60
|m = 60
|h = 830.8
|v = 0.97
|sv = 0.25
|discoverer = Dietrich Leithner
|discoveryear = 1996
|rulemin = B3/S23
|rulemax = B3/S238
|rulespecial = [[Conway's Game of Life|Conway Life]]
|isorulemin = B3/S23
|isorulemax = B34e/S234ce5ek6e8
|plaintext = true
|rle = true
|animated = true
|viewerconfig = #C [[ GPS 20 LOOP 60 THUMBSIZE 2 HEIGHT 480 WIDTH 480 AUTOSTART OFF ]]
|hideimg = true
|apgcode = xp60_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
}}
'''Star gate''' is a [[pattern]] based on the [[Fast forward force field]] that was created on October 26, {{year|1996}} by [[Dietrich Leithner]]. It is a [[period]] 60 [[oscillator]] that allows [[lightweight spaceship]]s to jump forward at the [[superluminous]] [[speed]] of 15c/14. Specifically, lightweight spaceships entering from the left appear to jump by 30 [[cell]]s along their path in 28 [[generation]]s.
{{gallery top}}
{{gallery item|{{EmbedViewer
|pname = stargate
|viewerconfig = #C [[ HEIGHT 600 WIDTH 800 THUMBSIZE 2 ZOOM 4 ]]
|position = center
|caption = The pattern
|style = width:300px;
}}}}
{{gallery item|{{EmbedViewer
|pname = stargateteleporting
|viewerconfig = #C [[ HEIGHT 600 WIDTH 800 THUMBSIZE 2 ZOOM 4 GPS 30 AUTOSTART T 0 PAUSE 3 T 180 PAUSE 2 LOOP 181 ]]
|position = center
|caption = Animation of a star gate teleporting some lightweight spaceships
|style = width:300px;
}}}}
{{gallery bottom}}

==See also==
* [[Diagonal lightspeed communication]]

==External links==
* {{LinkLexicon|lex_s.htm#stargate}}
* {{LinkCatagolue|xp60_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|format=extended}}

Superluminous

2023-10-08T10:36:33Z

Apple Bottom: Created page with "{{Glossary}} A speed is said to be '''superluminous''' if it exceeds the speed of light, ''c''. Just as in real life, information cannot be transmitted faster than the speed of light in Conway's Game of Life; there are, however, patterns that give the illusion of this happening, with the fast forward force field and the star gate built on it being prominent examples."

{{Glossary}}
A [[speed]] is said to be '''superluminous''' if it exceeds the [[speed of light]], ''c''. Just as in real life, information cannot be transmitted faster than the speed of light in [[Conway's Game of Life]]; there are, however, patterns that give the illusion of this happening, with the [[fast forward force field]] and the [[star gate]] built on it being prominent examples.

Neutronic

2022-05-29T18:54:45Z

Apple Bottom: Redirected page to Neutronium

#REDIRECT [[Neutronium]]

Neutronium

2022-05-29T18:54:22Z

Apple Bottom: /* Generalizations and variants */

{{Glossary}}
'''Neutronium''', in the context of multi-state [[Conway's Game of Life|Life]]-like [[cellular automata]], refers to an additional cell state that is permanently live. A cell in the "neutronium" state is also said to be '''neutronic'''. Informally, the term may also be used to refer to '''anti-neutronium''': a cell that is permanently dead.

==The ''Neutronium'' rule==
Neutronium was first considered by Mike Turniansky for a rule of the same name<ref name="thread1338" />. In this rule, cells can exist in three states, dead, live and neutronium, the last of which is considered "live"; [[evolution]] happens as in [[Conway's Game of Life]], except that a live cell surrounded by eight live neighbors (including neutronic neighbors) will itself turn into neutronium.

More precisely, patterns in this CA evolve according to the following rules:

# A dead cell:
## is born if it has precisely 5 dead neighbors (i.e. precisely 3 neighbors each of which is either live or neutronic).
# A live cell:
## turns into neutronium if it has precisely 0 dead neighbors;
## survives (remains live) if it otherwise has has precisely 5 or 6 dead neighbors;
## dies otherwise.
# A neutronic cell:
## remains neutronic.

Many small patterns evolve the same in Neutronium as they do in Conway's Game of Life; however, the [[HWSS]] is unstable, due to a neutronium cell forming, and the [[R-pentomino]] explodes:

{{Cquote|But the oddest surprise was the r-pentonimo [sic], which after 76,398 generations had a population of 86,158,122, including an estimated 20,000 gliders flying out in four huge sparse triangular formations (and about 20 orthogonal spaceships), fleeing a central seething ball of neutronioum [sic] growing at a rate of about 2/11c[.]|author=Mike Turniansky}}

===Generalizations and variants===
Neutronium can be generalized in a straightforward manner to [[outer-totalistic]] rules other than Conway's Game of Life (B3/S23). Many ''neutronic'' automata created this way exhibit explosive behavior, but not all do; B3/S2-Neutronium, for instance, is stable.

Other variants of the rule were created by 'c0b0p0' and [[Alexey Nigin]].

==See also==
* [[BSFKL]]
* [[Generations]]

==References==
<references>
<ref name="thread1338">{{LinkForumThread
|f = 11
|t = 1338
|accessdate = March 21, 2018
|date = March 10, 2014
|title = R-pentomino neutronium
|author = Mike Turniansky
|format = ref
}}</ref>
</references>

==External links==
{{LinkWikipedia|Neutronium}} (the term)

__NOTOC__
[[Category:Cellular automata]]

Neutronium

2022-05-29T17:09:07Z

Apple Bottom:

{{Glossary}}
'''Neutronium''', in the context of multi-state [[Conway's Game of Life|Life]]-like [[cellular automata]], refers to an additional cell state that is permanently live. A cell in the "neutronium" state is also said to be '''neutronic'''. Informally, the term may also be used to refer to '''anti-neutronium''': a cell that is permanently dead.

==The ''Neutronium'' rule==
Neutronium was first considered by Mike Turniansky for a rule of the same name<ref name="thread1338" />. In this rule, cells can exist in three states, dead, live and neutronium, the last of which is considered "live"; [[evolution]] happens as in [[Conway's Game of Life]], except that a live cell surrounded by eight live neighbors (including neutronic neighbors) will itself turn into neutronium.

More precisely, patterns in this CA evolve according to the following rules:

# A dead cell:
## is born if it has precisely 5 dead neighbors (i.e. precisely 3 neighbors each of which is either live or neutronic).
# A live cell:
## turns into neutronium if it has precisely 0 dead neighbors;
## survives (remains live) if it otherwise has has precisely 5 or 6 dead neighbors;
## dies otherwise.
# A neutronic cell:
## remains neutronic.

Many small patterns evolve the same in Neutronium as they do in Conway's Game of Life; however, the [[HWSS]] is unstable, due to a neutronium cell forming, and the [[R-pentomino]] explodes:

{{Cquote|But the oddest surprise was the r-pentonimo [sic], which after 76,398 generations had a population of 86,158,122, including an estimated 20,000 gliders flying out in four huge sparse triangular formations (and about 20 orthogonal spaceships), fleeing a central seething ball of neutronioum [sic] growing at a rate of about 2/11c[.]|author=Mike Turniansky}}

===Generalizations and variants===
Neutronium can be generalized in a straightforward manner to [[outer-totalistic]] rules other than Conway's Game of Life (B3/S23). Variants of the rule were created by 'c0b0p0' and [[Alexey Nigin]].

==See also==
* [[BSFKL]]
* [[Generations]]

==References==
<references>
<ref name="thread1338">{{LinkForumThread
|f = 11
|t = 1338
|accessdate = March 21, 2018
|date = March 10, 2014
|title = R-pentomino neutronium
|author = Mike Turniansky
|format = ref
}}</ref>
</references>

==External links==
{{LinkWikipedia|Neutronium}} (the term)

__NOTOC__
[[Category:Cellular automata]]

Talk:Bit-reading glider

2022-05-29T16:38:03Z

Apple Bottom: Created page with "Re: the suggested merge, see Talk:Epicentre. ~~~~"

Re: the suggested merge, see [[Talk:Epicentre]]. [[User:Apple Bottom|Apple Bottom]] ([[User talk:Apple Bottom|talk]]) 16:38, 29 May 2022 (UTC)

Talk:Aeon

2022-05-29T16:37:53Z

Apple Bottom: Created page with "Re: the suggested merge, see Talk:Epicentre. ~~~~"

Re: the suggested merge, see [[Talk:Epicentre]]. [[User:Apple Bottom|Apple Bottom]] ([[User talk:Apple Bottom|talk]]) 16:37, 29 May 2022 (UTC)

Talk:Parsec

2022-05-29T16:37:49Z

Apple Bottom: Created page with "Re: the suggested merge, see Talk:Epicentre. ~~~~"

Re: the suggested merge, see [[Talk:Epicentre]]. [[User:Apple Bottom|Apple Bottom]] ([[User talk:Apple Bottom|talk]]) 16:37, 29 May 2022 (UTC)

Talk:Epicentre

2022-05-29T16:37:28Z

Apple Bottom: Created page with "Re: the suggested merge, I'm all in favor of explaining related concepts in a more general article (RCT in this case), but I also think that the whole point of the ''Glossary'' section (which is conceptually based on the Lexicon, of course) is to have small, self-contained explanations of concepts and keywords, so unless we want to forego that and abandon this approach I'd suggest to refrain from merging. ~~~~"

Re: the suggested merge, I'm all in favor of explaining related concepts in a more general article (RCT in this case), but I also think that the whole point of the ''Glossary'' section (which is conceptually based on the Lexicon, of course) is to have small, self-contained explanations of concepts and keywords, so unless we want to forego that and abandon this approach I'd suggest to refrain from merging. [[User:Apple Bottom|Apple Bottom]] ([[User talk:Apple Bottom|talk]]) 16:37, 29 May 2022 (UTC)

Books

2022-05-29T16:33:45Z

Apple Bottom: Cat redir (for now, feel free to replace with an article)

#REDIRECT [[:Category:Books and articles]]

Talk:Extended Generations

2022-05-29T16:25:40Z

Apple Bottom: Created page with "The description can't be right, in that it never uses the D''d'' part of the rulestring; maybe someone can fix this. While you're at it, some examples would also be nice, as would be a better explanation of ''how exactly'' "the last segment, ''d'', specifies ranges of activity/inactivity". ~~~~"

The description can't be right, in that it never uses the D''d'' part of the rulestring; maybe someone can fix this. While you're at it, some examples would also be nice, as would be a better explanation of ''how exactly'' "the last segment, ''d'', specifies ranges of activity/inactivity". [[User:Apple Bottom|Apple Bottom]] ([[User talk:Apple Bottom|talk]]) 16:25, 29 May 2022 (UTC)

Extended Generations

2022-05-29T16:23:44Z

Apple Bottom: Formatting

{{Glossary}}
'''Extended Generations''' rules are a generalization of [[Generations]] rules. This extension explores the result of changing the amounts of time cells can be active/inactive for, and also of allowing cells to "come back" from inactivity and alternate between being active/inactive an indefinite amount of times before dying.

They were conceived by users [[DigitalCross]] and later [[Milo Jacquet]].<ref name="post62255"/>

==Description==
Extended Generations rules are described by [[rulestring]]s in the form B''b''/S''s''/D''d''; where ''b'' and ''s'' are numbers between 0 - 8. The last segment, ''d'', specifies ranges of activity/inactivity, starting with the former and then alternating.

We write ''n'' ∈ ''B'', ''n'' ∈ ''S'' if ''n'' is one of the numbers in ''b'', ''s''; patterns then evolve according to the following rules:

# An active cell:
## remains in its current state if ''n'' ∈ ''S'';
## advances to state ((''x'' + 1) mod ''y'') in the next generation of the pattern otherwise, where ''x'' is the current state of the cell and ''y'' is the total number of states in the rule
# An inactive cell:
## advances to state ((''x'' + 1) mod ''y'') in the next generation of the pattern otherwise, where ''x'' is the current state and ''y'' is the total number of states, i.e. behaves like a normal [[Generations]] dying cell.
# A dead cell:
## advances to state 1 if ''n'' ∈ B;
## remains dead otherwise.

[[Generations]] and snoitareneG<ref name="thread2939"/><ref name="thread372"/><ref name="post44058"/> can be considered subsets of the Extended Generations rulespace.<ref name="post62255"/>

==Software support==
Extended Generations rules are not natively supported by either [[Golly]] or [[LifeViewer]] (support is planned for the latter),<ref name="post68691" /> but can be run with a suitable ruletable on either. [[Catagolue]] and [[apgsearch]] natively support Extended Generations rules.<ref>{{cite web|url=https://gitlab.com/apgoucher/apgmera/-/commit/a5812bb36a3f2d40b7fbf630f90546bbf1bf1fe4|title=Native support for Extended Generations and Deficient rules courtesy of M. I. Wright|author=Adam P. Goucher|date=January 15, 2019|work=GitLab}}</ref>

==References==
<references>
<ref name="thread372">{{LinkForumThread
|title = "Reverse Generations" Rules
|format = ref
|t = 372
|author = Martin Grant
|date = April 10, 2010
}}</ref>
<ref name="thread2939">{{LinkForumThread
|title = snoitareneG Rules
|format = ref
|t = 2939
|author = Saka
|date = July 2, 2017
}}</ref>
<ref name="post44058">{{LinkForumThread
|title = Re: Thread for basic questions
|author = Brian Prentice
|date = June 4, 2017
|format = ref
|p = 44058
|t = 2036
|f = 7
}}</ref>
<ref name="post62255">{{LinkForumThread
|format = ref
|title = "Extended" Generations rules
|p = 62255
|author = M. I. Wright
|date = August 1, 2018
}}</ref>
<ref name="post68691">{{LinkForumThread
|format = ref
|title = Re: Pattern viewer for forum threads
|p = 68691
|author = Chris Rowett
|date = January 26, 2019
}}</ref>
</references>

[[Category:Algorithms]]
[[Category:Cellular automata]]
[[Category:Generations| ]]

Peter Naszvadi

2022-05-29T16:16:39Z

Apple Bottom:

{{Person
|name = Peter Naszvadi
|res = Hungary
|nat = Hungarian
}}{{For|Peter Naszvadi's userpage|User:Naszvadi}}
'''Peter Naszvadi''' is an active contributor on the ConwayLife.com forums, particularly in [[OCA]]-related topics.

In March 2020 he discovered a [[c/5_diagonal#Puffers|c/5 diagonal period-1540 puffer]], based on three copies of [[58P5H1V1]]. He has also proved many [[CA]]s, most notably [[Seeds]], [[DryLife]] and [[Life without death]], [[Turing-complete]]. Many of the proofs involve the direct construction of a [[Rule 110]] [[unit cell]].

{{DEFAULTSORT:Naszvadi, Peter}}

Photon

2022-05-29T16:15:05Z

Apple Bottom:

{{Glossary}}
A '''photon''' is a [[spaceship]] moving at the [[speed of light]]. Photons are not possible in [[Conway's Game of Life]], in which the maximum speed of a [[slope]]-''n'' spaceship is ''c/(2n+2)''; they do, however, exist in other Life-like rules, for example [[Seeds]] or [[Live Free or Die]].

{{EmbedViewer
|viewerconfig = #C [[ THEME 6 GRID GRIDMAJOR 0 THUMBLAUNCH AUTOSTART GPS 4 THUMBSIZE 2 TRACKLOOP 1 -1 0 ]]
|caption = The [[grin|moon]] is a common photon in many B2 rules. 
|position = center
|rle =
x = 2, y = 4, rule = B2/S
bo$o$o$bo!
}}

==Also see==
* [[Grin]]

Yoel Matveyev

2022-05-29T16:11:17Z

Apple Bottom: We don't need to say "he's notable", that's readily apparent; just list what he did. Also, some links to invite new articles to be written, etc.

{{Person
|name = Yoel Matveyev
|nat = Russian
}}

'''Yoel Matveyev''' is a Russian science fiction writer, poet, software developer and a cellular automata enthusiast. In 2021 he released<ref name="post136309" /> the largest known cellular automation computer called [[Izhora]] based on his own 4-state rule [[OCA:FireWorld|FireWorld]]. It has 256 kilobytes of memory, a 256x128 memory-mapped pixel display and a keyboard driven by a script. Its 32-bit CPU uses a single operation, subtract and branch if zero or negative (SUBLEQ), from which all other operations can be synthesized. Examples include 256-bit [[factorial]]s, [[prime number|prime]]s and [[Fibonacci number]]s. Tools such as an assembler and emulator are provided for programming it.

Matveyev is also proved [[Turing completeness]] of [[OCA:Brian's Brain|Brian's Brain]] in 2020, <ref name="post110762" /> and investigated multistate cyclical rules, which can be viewed as generalizing the notion of [[Self-complementary|self-complementarity]]. In multistate cyclic rules every pattern behaves exactly the same, if the states of all live cells are cyclically changed to one another, e.g. 1→2,2→3,3→1<ref name="post101012" />.

==References==
<references>
<ref name="post136309">{{LinkForumThread
|p = 136309
|format = ref
|title = Izhora (Fireworld2 computer)
|author = Yoel Matveyev
|date = October 5, 2021
}}</ref>
<ref name="post110762">{{LinkForumThread
|p = 110762
|format = ref
|title = Re: Turing - complete Generations rules
|author = Yoel Matveyev
|date = November 15, 2020
}}</ref>
<ref name="post101012">{{LinkForumThread
|format = ref
|title = Re: Gluonic
|p = 101012
|author = Yoel Matveyev
|date = July 24, 2020
}}</ref>
</references>

BSRD

2022-05-29T15:35:36Z

Apple Bottom: Something else to write

#REDIRECT [[Binary Storage and Retrieval Device]]

Decoder and Better Construction Arm

2022-05-29T15:33:39Z

Apple Bottom: Someone else will have to write this

In [[reverse caber tosser]] technology, the '''Decoder and Better Construction Arm''' ('''DBCA''') is, somewhat informally, an optional stage of the RCT that allows building much more complex [[object]]s with the same number of [[bit]]s encoded in the RCT distance.

On May 7, 2022, [[Adam P. Goucher]] built an example DBCA that fit in a 995×876 bounding box.<ref name="post145213" />

==References==
<references>
<ref name="post145213">
{{LinkForumThread
|format = ref
|title = Re: Chapman-Greene construction arm
|p = 145213
|author = Adam P. Goucher
|date = May 7, 2022
}}
</ref>
</references>

==See also==
*[[Chapman-Greene construction arm]]
*[[Goucher-Grankovskiy construction arm]]
*[[Actual Thing Being Constructed]]

==External links==
* Dave Greene, [https://b3s23life.blogspot.com/2022/04/current-rct-technology-part-1-build.html Current RCT Technology, Part 1 (Build Anything Constructible, Now With Just 16 Gliders)], April 24 2022
* Dave Greene, [https://b3s23life.blogspot.com/2022/05/current-rct-technology-part-2-dbca.html Current RCT Technology, Part 2: the DBCA (Decoder and Better Construction Arm)], May 29 2022

{{Glossary}}

Chapman-Greene construction arm

2022-05-29T15:33:25Z

Apple Bottom: Someone else will have to write this

The '''Chapman-Greene Construction Arm''' is a programmable [[construction arm]] built in May 2004 by [[Paul Chapman]] and [[Dave Greene]].<ref name="post141232" />

In May 2022, [[Adam P. Goucher]] rebuilt the Chapman-Greene Construction Arm using up-to-date [[spartan]] technology.<ref name="post145133" />

==Method==
[[Signal]]s prompt the [[universal constructor]] to pull the construction arm's [[elbow]] closer, push it farther away, or shoot a glider of either color sideways from the elbow's current position. The choice of operations--PUSH, PULL, the two FIRE recipes, or a SHUT DOWN signal--is made by reading a static tape where one to five 1's ([[boat]]s) are stored in unary, separated by zeroes ([[block]]s).

==See also==
*[[Goucher-Grankovskiy construction arm]]
*[[Universal constructor]]
*[[Gemini]]
*[[Oblique spaceship]]

==References==
<references>
<ref name="post141232">{{LinkForumThread
|format = ref
|title = Re: Thread for basic questions
|p = 141232
|author = Dave Greene
|date = February 4, 2022
}}</ref>
<ref name="post145133">{{LinkForumThread
|format = ref
|title = Re: Chapman-Greene construction arm
|p = 145133
|author = Dave Greene
|date = May 5, 2022
}}</ref>
</references>

Decoder and Better Construction Arm

2022-05-29T15:32:24Z

Apple Bottom:

In [[reverse caber tosser]] technology, the '''Decoder and Better Construction Arm''' ('''DBCA''') is, somewhat informally, an optional stage of the RCT that allows building much more complex [[object]]s with the same number of [[bit]]s encoded in the RCT distance.

On May 7, 2022, [[Adam P. Goucher]] built an example DBCA that fit in a 995×876 bounding box.<ref name="post145213" />

==References==
<references>
<ref name="post145213">
{{LinkForumThread
|format = ref
|title = Re: Chapman-Greene construction arm
|p = 145213
|author = Adam P. Goucher
|date = May 7, 2022
}}
</ref>
</references>

==See also==
*[[Chapman-Greene construction arm]]
*[[Actual Thing Being Constructed]]

==External links==
* Dave Greene, [https://b3s23life.blogspot.com/2022/04/current-rct-technology-part-1-build.html Current RCT Technology, Part 1 (Build Anything Constructible, Now With Just 16 Gliders)], April 24 2022
* Dave Greene, [https://b3s23life.blogspot.com/2022/05/current-rct-technology-part-2-dbca.html Current RCT Technology, Part 2: the DBCA (Decoder and Better Construction Arm)], May 29 2022

{{Glossary}}

ATBC

2022-05-29T15:32:13Z

Apple Bottom: Redirected page to Actual Thing Being Constructed

#REDIRECT [[Actual Thing Being Constructed]]

Actual Thing Being Constructed

2022-05-29T15:32:08Z

Apple Bottom: Created page with "In reverse caber tosser technology, the '''Actual Thing Being Constructed''' ('''ATBC''') is the final object that the RCT recipe is supposed to create. The term stands in contrast to the “scaffolding” that is used to aid in the construction but that is destroyed again when the construction completes. ==See also== *Decoder and Better Construction Arm ==External links== * Dave Greene, [https://b3s23life.blogspot.com/2022/04/current-rct-technology..."

In [[reverse caber tosser]] technology, the '''Actual Thing Being Constructed''' ('''ATBC''') is the final [[object]] that the RCT recipe is supposed to create. The term stands in contrast to the “scaffolding” that is used to aid in the construction but that is destroyed again when the construction completes.

==See also==
*[[Decoder and Better Construction Arm]]

==External links==
* Dave Greene, [https://b3s23life.blogspot.com/2022/04/current-rct-technology-part-1-build.html Current RCT Technology, Part 1 (Build Anything Constructible, Now With Just 16 Gliders)], April 24 2022
* Dave Greene, [https://b3s23life.blogspot.com/2022/05/current-rct-technology-part-2-dbca.html Current RCT Technology, Part 2: the DBCA (Decoder and Better Construction Arm)], May 29 2022

{{Glossary}}

Decoder and Better Construction Arm

2022-05-29T15:27:09Z

Apple Bottom:

In [[reverse caber tosser]] technology, the '''Decoder and Better Construction Arm''' ('''DBCA''') is, somewhat informally, an optional stage of the RCT that allows building much more complex [[object]]s with the same number of [[bit]]s encoded in the RCT distance.

On May 7, 2022, [[Adam P. Goucher]] built an example DBCA that fit in a 995×876 bounding box.<ref name="post145213" />

==References==
<references>
<ref name="post145213">
{{LinkForumThread
|format = ref
|title = Re: Chapman-Greene construction arm
|p = 145213
|author = Adam P. Goucher
|date = May 7, 2022
}}
</ref>
</references>

==See also==
*[[Chapman-Greene construction arm]]

==External links==
* Dave Greene, [https://b3s23life.blogspot.com/2022/04/current-rct-technology-part-1-build.html Current RCT Technology, Part 1 (Build Anything Constructible, Now With Just 16 Gliders)], April 24 2022
* Dave Greene, [https://b3s23life.blogspot.com/2022/05/current-rct-technology-part-2-dbca.html Current RCT Technology, Part 2: the DBCA (Decoder and Better Construction Arm)], May 29 2022

{{Glossary}}

Decoder and Better Construction Arm

2022-05-29T15:26:50Z

Apple Bottom:

In [[reverse caber tosser]] technology, the '''Decoder and Better Construction Arm''' ('''DBCA''') is, somewhat informally, an optional stage of the RCT that allows building much more complex [[object]]s with the same number of [[bit]]s encoded in the RCT distance.

On May 7, 2022, [[Adam P. Goucher]] built an example DBCA that fit in a 995×876 bounding box.<ref name="post145213" />

==References==
<references>
<ref name="post145213">
{{LinkForumThread
|format = ref
|title = Re: Chapman-Greene construction arm
|p = 145213
|author = Adam P. Goucher
|date = May 7, 2022
}}
</ref>
</references>

==See also==
*[[Chapman-Greene construction arm]]

==External links==
* Dave Greene, [https://b3s23life.blogspot.com/2022/04/current-rct-technology-part-1-build.html Current RCT Technology, Part 1 (Build Anything Constructible, Now With Just 16 Gliders)], April 24 2022
* Dave greene, [https://b3s23life.blogspot.com/2022/05/current-rct-technology-part-2-dbca.html Current RCT Technology, Part 2: the DBCA (Decoder and Better Construction Arm)], May 29 2022

{{Glossary}}