Search found 29 matches

by andrewthelifer
August 6th, 2026, 6:51 am
Forum: General Discussion
Topic: Strangest CA-related mathematical coincidences?
Replies: 24
Views: 21860

Re: Strangest CA-related mathematical coincidences?

As you likely know, there are exactly 2^18 outer-totalistic CA on the 1-Moore neighbourhood -- 9 transitions of quantity (012345678) independently in Birth and Survival.

Suppose you have a 4-state Von Neumann automaton with the restriction that it must be isotropic on the grid and that all 24 ...
by andrewthelifer
August 5th, 2026, 4:32 pm
Forum: General Discussion
Topic: Create your own terminology
Replies: 505
Views: 265925

Re: Create your own terminology

A 2-state cellular automaton has exactly two types of colour invariance: none (as in Life) and self-complement (as in Day and Night ).

3-state CA admit four types of colour invariance, corresponding to the subgroups of the group of permutations on 3 elements up to conjugacy (so that 1<->2 and 1<->3 ...
by andrewthelifer
August 5th, 2026, 10:21 am
Forum: General Discussion
Topic: Thread for advanced questions
Replies: 206
Views: 51309

Re: Thread for advanced questions

B/S01 has three still-lives: the dot, domino and duoplet.

Out of all INT rules that have only finitely many still-lives of finite population, do any of them have more finite SLs?
by andrewthelifer
August 4th, 2026, 8:49 pm
Forum: Other Cellular Automata
Topic: Spaceships made up of other spaceships (SMOS)
Replies: 331
Views: 179081

Re: Spaceships made up of other spaceships (SMOS)

Which is the closest INT rule to Life (by transitions different from B3/S23) where a two-glider SMOS is known to exist and the glider otherwise moves identically to Life?
by andrewthelifer
August 4th, 2026, 6:39 pm
Forum: Other Cellular Automata
Topic: Thread for your corderization requests
Replies: 540
Views: 102138

Re: Thread for your corderization requests

On behalf of Leriendil/majestaz, a (10,3)c/149 puffer that should be corderisable:

Code: Select all

x = 23, y = 13, rule = B2-a3c/S12-i
20bobo2$10bobo$11bo$11bo8$obo!
by andrewthelifer
August 3rd, 2026, 7:29 am
Forum: General Discussion
Topic: Unproven conjectures
Replies: 555
Views: 300869

Re: Unproven conjectures

[catagolue][/catagolue]
The pre-block is a counterexample for both conjectures:
x = 2, y = 2, rule = B3/S23
2A$.A!


You've done it! And of course the reward of a taskmaster to his subjects is to set them another task.

A spirited pattern in Life is a pattern where all live cells have 2 or 3 ...
by andrewthelifer
August 1st, 2026, 10:09 am
Forum: General Discussion
Topic: Unproven conjectures
Replies: 555
Views: 300869

Re: Unproven conjectures

A lively pattern in Life is a pattern where every live cell survives to the next generation (because they all have 2 or 3 live neighbours). By this definition, still-lives are the lively patterns where no dead cell has exactly 3 neighbours so no birth can occur.

The above describes 1-lively ...
by andrewthelifer
August 1st, 2026, 9:58 am
Forum: General Discussion
Topic: Create your own terminology
Replies: 505
Views: 265925

Re: Create your own terminology

A lively pattern in a no-B0 MAP CA is one whose live cells will all stay live in the next generation, although some may be born. As all still lives are lively by this definition, we will write them out of it by fiat: inductees in Life are thus the only "lively" patterns Life is considered to have ...
by andrewthelifer
February 27th, 2026, 2:23 pm
Forum: Other Cellular Automata
Topic: Thread for basic non-CGOL questions
Replies: 1683
Views: 478827

Re: Thread for basic non-CGOL questions

B468S02357 wrote: February 18th, 2026, 5:40 pm What type of pattern is this?

Code: Select all

x = 19, y = 23, rule = R3,C2,S8-10,18,20-24,B4,10-13,NN
bo$o$o2b2o$o3bo$4bobo$o5b2o$6bo$2bo2bo$bo2bo9$14bo$17bo2$13bo4bo$13b3o
b2o$17bo!
Seems to be a replicator with many diferent copies out of phase with each other.
by andrewthelifer
October 14th, 2025, 9:19 am
Forum: General Discussion
Topic: Create your own terminology
Replies: 505
Views: 265925

Re: Create your own terminology


I think the quotation marks around "soup" were important in the original definition.

Predecessors that aren't randomly generated are not really soups. So there can't be a soup that not's randomly generated -- but there can be a "soup" that's not randomly generated (because it looks just like a ...
by andrewthelifer
September 20th, 2025, 11:00 am
Forum: General Discussion
Topic: Poetic coincidences
Replies: 8
Views: 2427

Re: Poetic coincidences

The fully universal Turing machine, demonstrating that the evolution of finite patterns in Life was as hard as the halting problem, was finished on March 23rd aka 23/3 (or 3/23 with missing B and S).
by andrewthelifer
September 19th, 2025, 5:17 am
Forum: Other Cellular Automata
Topic: Spaceships made up of other spaceships (SMOS)
Replies: 331
Views: 179081

Re: Spaceships made up of other spaceships (SMOS)


I think I solved the bonus.

2c/127d which has both a u-pentomino ship and the t-ship from traveling ts.
x = 7, y = 7, rule = B2ei3-ckry4enqr6aei8/S2-n3eiry4nwyz5acin6akn7c
2o$bo$2o3$4b3o$4bobo!
x = 8, y = 8, rule = B2ei3-ckry4enqr6aei8/S2-n3eiry4nwyz5acin6akn7c
bo$2o$bo4$5b3o$6bo!



This ...
by andrewthelifer
August 28th, 2025, 6:07 am
Forum: Patterns
Topic: Thread for your unsure discoveries
Replies: 4029
Views: 1912433

Re: Thread for your unsure discoveries

Has this dirty replicator been discovered?

Code: Select all

x = 5, y = 6, rule = B3/S23:T0,6
$2bo$bobo$o3bo$bobo$2bo!
As it turns out yes, it's in the titanic toroidal traveler.
by andrewthelifer
August 24th, 2025, 6:06 pm
Forum: General Discussion
Topic: Create your own terminology
Replies: 505
Views: 265925

Re: Create your own terminology

One can formalise a shooter to be any finite periodic pattern for which Generation N is identical to G0 except that some periodic debris is present at generation N, with catapults being those shooters whose cores undergo 0 displacement from shot to shot, and firearms undergoing some displacement ...
by andrewthelifer
August 24th, 2025, 9:07 am
Forum: General Discussion
Topic: Create your own terminology
Replies: 505
Views: 265925

Re: Create your own terminology

Elaborating existing terminology:

Minimal definition of SMOS: a spaceship which is decomposable as "made of spaceships" and vacuum in at least one phase, and isn't MOS+vacuum in some other phase,

Restrictions on decomposability give increasingly specific and "natural" SMOSes within 2-state ...
by andrewthelifer
August 24th, 2025, 7:50 am
Forum: General Discussion
Topic: Thread for advanced questions
Replies: 206
Views: 51309

Re: Thread for advanced questions

INT's most supported...
  • still-life: the dot (2^98 rules: forced S0 and no B0, B1e, B1c)
  • oscillator: the duoplet (2^97 rules: forced B2e and no B0, B1e, B1c, S1c)
  • spaceship: the p1 moon (2^94 rules: forced B2a, B2e and no B0, B1e, B1c, S1c, S2k)
What is INT's most supported gun?
by andrewthelifer
August 23rd, 2025, 6:15 pm
Forum: General Discussion
Topic: Thread for advanced questions
Replies: 206
Views: 51309

Re: Thread for advanced questions

Is there a pattern which:
  • fits in a finite bounding box
  • is rotationally asymmetric
  • is never a spaceship when run in any INT CA?
Or is there a proof against the existence of such a pattern?
by andrewthelifer
August 23rd, 2025, 3:24 pm
Forum: Other Cellular Automata
Topic: Thread for basic non-CGOL questions
Replies: 1683
Views: 478827

Re: Thread for basic non-CGOL questions

PK22 wrote: August 23rd, 2025, 1:12 pm
Resu wrote: August 23rd, 2025, 11:19 am How do you find the maximum speed of spaceships in each rule?
[...]contains B3 and (rule contains S4 or S5): Maximum speed is (x, y)c/2*max(x, y) + min(x, y).[...]
Is this speed accurately represented as (x,y)c/(2*max(x,y) + min(x,y))? <note extra brackets>
by andrewthelifer
August 23rd, 2025, 9:57 am
Forum: Help / Support
Topic: Thread for basic questions
Replies: 6120
Views: 2054378

Re: Thread for basic questions


What types of pattern are known to exist in CGoL thanks to universal construction/0E0P emulation, but have not been explicitly constructed?


Any pattern in INT also exists in Life at a step-size of 2^36 thanks to 0E0P -- including any type of SMOSMOS, replicator, binary counter, Rule 110 or ...
by andrewthelifer
August 23rd, 2025, 5:16 am
Forum: Other Cellular Automata
Topic: Spaceships made up of other spaceships (SMOS)
Replies: 331
Views: 179081

Re: Spaceships made up of other spaceships (SMOS)


1) Does a two-recipe SMOS exist?

2) Do n-recipe SMOSes exist for n > 2?


NimbleRogue has exhibited an isotropic rule with a 79c/13756 pi-only SMOS evolving into at least four recipes: arrangements of two, four, seven, four pis respectively, both "four" arrangements different in their ...
by andrewthelifer
August 22nd, 2025, 12:32 pm
Forum: The Sandbox
Topic: how and when you discovered the game of life?
Replies: 88
Views: 85576

Re: how and when you discovered the game of life?

I saw Michael Stevens of Vsauce mention it, played with it for some years then got into it seriously in 2019 with Golly and this site.
by andrewthelifer
August 22nd, 2025, 8:37 am
Forum: Other Cellular Automata
Topic: Spaceships made up of other spaceships (SMOS)
Replies: 331
Views: 179081

Re: Spaceships made up of other spaceships (SMOS)



1) Does a two-recipe SMOS exist?

2) Do n-recipe SMOSes exist for n > 2?

bonus: Is there a two-recipe SMOS where no spaceship in the first recipe appears in the second?

In which types of CA?


Two state INT.
Example of the bonus; a two-glider collision for which the crash creates a two ...
by andrewthelifer
August 22nd, 2025, 7:19 am
Forum: Other Cellular Automata
Topic: Spaceships made up of other spaceships (SMOS)
Replies: 331
Views: 179081

Re: Spaceships made up of other spaceships (SMOS)



1) Does a two-recipe SMOS exist?

Is "two-recipe SMOS" means a spaceship made of two different ship?


A spaceship which has two different phases at which there are two recipes. For example if you can find a SMOS with 3-glider and 5-glider phases in its evolution, or a glider+glider -> glider ...
by andrewthelifer
August 22nd, 2025, 7:17 am
Forum: General Discussion
Topic: Unproven conjectures
Replies: 555
Views: 300869

Re: Unproven conjectures


They are engineered spaceships, e.g. the c/18 in HighLife:[...]


This isn't a SMOI, because there's no small phase that becomes two of itself at any point. (actual SMOI by macbi for comparison)

I suspect universal construction allows arbitrary k-SMOSes, because self-making constructors could be ...
by andrewthelifer
August 22nd, 2025, 7:04 am
Forum: Other Cellular Automata
Topic: Spaceships made up of other spaceships (SMOS)
Replies: 331
Views: 179081

Re: Spaceships made up of other spaceships (SMOS)

A SMOS' recipe is the multiset of spaceships that make it up in its MOS phase, strictly defined as a phase with suitably separated spaceships and no other debris. Two recipes are different if they have different quantities (4 vs 7 gliders) or different types of spaceship.

A two-recipe SMOS has two ...