Thread for Your Interesting Rulegolf Starting Points

[rabbit]

This thread is for posting interesting potential starting points for rulegolfing sessions, so that others may derive their own rules from them, and to keep them saved somewhere. Ideally the base rule should have some small interesting object, but other desired properties are possible. The number of transitions that can be changed while preserving the key reactions should be rather high, though.

I'll start by sharing B35-n/S23-y4n, a three-transition Life variant which has a surprisingly clean 8-generation B-heptomino replication:

Code: Select all

x = 3, y = 4, rule = B35n/S23-y4n
o$2o$b2o$2o!

Removing B3n or B3q makes it a clean replicator, but there's plenty of other space to explore since the core reaction is so low-period.

-

Second, here's a four-transition Life variant which has a glider familiar eight and a 3c/9:

Code: Select all

x = 20, y = 5, rule = B34a/S23-a4nq
o14b3o$2b3o12b2o$2bobo14bo$bob2o12b2o$b2o12b3o!

There's probably ways to force other common diagonally-symmetric patterns to turn into it.

[hibiscus]

I've said this before, but I think B3aijqy4kw5cinry6ik/S2ik3ai4ar5ijnq6ac7e8 is an interesting starting point for rulegolfing.

Rulegolfing, using this rule as a base, also tends to be quite fruitful.
A few steps down the line, you'll find a p982 natural oscillator, among other things:

Code: Select all

x = 55, y = 24, rule = B3-cknr4kw5-aekq6ik/S2ik3ai4aqr5ijnq6ac7e8
26b3o6$27bo$26b3o$18b3o4b5o4b3o$3b2o3b3o5bobobo4b5o4bobobo5b3o3b2o$6bo
bo2bo3bo2b3o3bob3obo3b3o2bo3bo2bobo$o3b6obo2b4obobo2b3ob3o2bobob4o2bob
6o3bo$o3b6obo2b4obobo2b3ob3o2bobob4o2bob6o3bo$6bobo2bo3bo2b3o3bob3obo
3b3o2bo3bo2bobo$3b2o3b3o5bobobo4b5o4bobobo5b3o3b2o$18b3o4b5o4b3o$26b3o
$27bo6$26b3o!

+B4a turns the failedrep into a p49:

Code: Select all

x = 2, y = 3, rule = B3aijqy4akw5cinry6ik/S2ik3ai4ar5ijnq6ac7e8
2o$2o$2o!

The main highlight, in my opinion, is the c/73 orthogonal.

Code: Select all

x = 28, y = 20, rule = B3aijqy4kw5cinry6ik/S2ik3ai4ar5ijnq6ac7e8
15b2o$15b2o6$5bo16bo$3bo3bo12bo3bo$2bo5bo10bo5bo$5bo7b2o7bo$b3obob3o3b
2o3b3obob3o$11obo2bob11o$b3obob3ob6ob3obob3o$5bo5b6o5bo$2bo5bo10bo5bo$
3bo3bo3bo4bo3bo3bo$5bo16bo2$13b2o!

[R2INT]

I have collected a few rules that contain small c/2o spaceship that is likely to be common in the final rule:
[1] Rules that contain the following pattern as a c/2o:

Code: Select all

#C Press 'Change Rule' to test out different rules displayed in the codeboxes displayed below the patterns
x = 3, y = 2, rule = B2-a3ei/S12c3a
.o.$
o.o!

Code: Select all

B2ce3ei/S1c2c3a
B2ce3e/S1c2a
B2ce3ei/S2ac
B2ce3i/S1e2c
B2e3ei/S2ac
B2e3i/S1c2ce

[2] Rules that contain the following pattern as a c/2o:

Code: Select all

B2ci3aeknq/S12ek3-i
.o.$
ooo!

Code: Select all

B2c3ae/S1c3e
B2c3a5i/S2a3e
B3ai/S1e2i3i
B2c3aei/S1c3e
B2c3ai4i/S1e2a
B3ai/S2ae3i4i

[3] Rules that contain the following pattern as a c/2o:

Code: Select all

x = 3, y = 2, rule = B2ck3acijq/S2-c3-n4i
ooo$
o.o!

Code: Select all

B2c3ai/S2ae3ij4i
B2c3ai5i/S2e3i4i
B2ce3i/S1c2ce
B2ce3i5i/S2ace3n
B2ce3i5i/S2ce
B2e3i/S2-in

[CARuler]

counter (rulegolfed from diff rule)

Code: Select all

x = 5, y = 1, rule = B2en3einy8/S2-a34ackqy5ckny6ekn7e8
5o!

cool stuff there

[rabbit]

B2ci3ae4/S1c2c4 is a very dormant rule that contains orthogonal and diagonal spaceships.

Adding S5 keeps the c/4 diagonal spaceship and also adds this c/42 diagonal:

Code: Select all

x = 7, y = 6, rule = B2ci3ae4/S1c2c45
5bo$3bob2o$4b2o$b3o2bo$3o$bo!

Adding S56 keeps the c/4 diagonal spaceship, greatly increases the activity, and also adds this puffer:

Code: Select all

x = 51, y = 52, rule = B2ci3ae4/S1c2c456
49bo$48b3o$45b5o$46bob2o$46b2o$45b3o$45b3o$42b5o$43b2o$42bobo14$28bo$
25b5o$25bobo$25bob2o$17bo4b3obo$13bo3b2o4b2o$13bo2b2o5b2o$15b3o$15bo$
16b2o$17bo$14bobobobo$18bo$17b3o$17bo10$bobo$obobo$b3o$obobo$bobo!

2c/16 orthogonal, c/3 diagonal, 4c/12 diagonal:

Code: Select all

x = 7, y = 29, rule = B2ci3ae4/S1c2c456
3bo$b2o$4o$4bo$2bo6$4bo$2bo$2b2o2bo$2bobo$b5o$3o$bo6$3bo$bo$2b2o$2bobo
$b3o$3o$bo!

Unfortunately, this last rule is explosive on D2_x, in such a way that even searching a symmetry like D4_+2 still explodes.

Rules in the neighbourhood of this one might be interesting, this particular rule has a growing kite linear growth:

Code: Select all

x = 4, y = 10, rule = B2ci3aj4ak/S2a345-i
2b2o$2bo$b2o$bo$4o2$4o$bo$b2o$2bo!

[rabbit]

Here is a three transition life variant with c/2 movement engines similar to Life. For spaceships, it has some very common small c/2s and the c/4 diagonal "ant" glider.

Unfortunately the base rule contains this nasty 78c/420 diagonal puffer:

Code: Select all

x = 5, y = 5, rule = B3-n/S234q5q
b2obo$bobo$o3bo$b2o$b2o!

Pseudo- ruler sequence growth in a related rule:

Code: Select all

x = 12, y = 23, rule = B3-n/S23-e4q5q
b2o$b3o$o2bo$ob2o$b2o14$9b2o$8bobo$8bo2bo$9b2o$10bo!

[rabbit]

Some time ago while researching near-totalistic rules, I noticed that the +B8 transition creates an almost replicator if used in conjunction with -S3q:

Code: Select all

x = 2, y = 3, rule = B38/S23-q
o$2o$o!

It creates a massive still life in the end as well.

This behaviour is mirrored if S5y replaces B8, but they diverge significantly afterward:

Code: Select all

x = 2, y = 3, rule = B3/S23-q5y
o$2o$o!

Both of the resulting rules were apgsearched long ago, but appear not to have been researched further in depth. They make excellent rulegolf starting points, though.

Adding +B6a yields a rule that seems stable at first glance, but can explode quickly:

Code: Select all

x = 67, y = 7, rule = B36a8/S23-q
o59bo$2o58b2o$o59bo3$65bo$65b2o!

[I6_I6]

Adding +B6a yields a rule that seems stable at first glance, but can explode quickly:

Code: Select all

x = 67, y = 7, rule = B36a8/S23-q
o59bo$2o58b2o$o59bo3$65bo$65b2o!

R is c/14d:

Code: Select all

x = 3, y = 3, rule = B36a8/S23-q
bo$3o$2bo!

EDIT:
A couple of natural oscs:

Code: Select all

x = 11, y = 12, rule = B36a8/S23-q
b3o3b3o$o9bo$b3o3b3o5$bo4bo$2bo2bo$bo4bo$2bo2bo$bo4bo!

[UnbihexiumFan]

I've been using B2ce/S14t as a starting point as it features a small ship as well as an eating reaction with said ship:

Code: Select all

x = 2, y = 7, rule = B2cei/S14t
o$o$bo3$o$o!

I've made a lot of discoveries in rules with this eating reaction, some of which I have already posted in Misc. Discoveries in OCA.

[I6_I6]

I've been using B2ce/S14t as a starting point as it features a small ship as well as an eating reaction with said ship:

Code: Select all

x = 2, y = 7, rule = B2cei/S14t
o$o$bo3$o$o!

I've made a lot of discoveries in rules with this eating reaction, some of which I have already posted in Misc. Discoveries in OCA.

There's also a second eating reaction:

Code: Select all

x = 5, y = 7, rule = B2cei/S14t
3bo$3bo$4bo3$o$o!

And a second small ship (2c/4):

Code: Select all

x = 3, y = 6, rule = B2cei/S14t
bo$obo4$bo!

[b-engine]

I've been using B2cei/S14t as a starting point as it features a small ship as well as an eating reaction with said ship:

Code: Select all

x = 2, y = 7, rule = B2cei/S14t
o$o$bo3$o$o!

I've made a lot of discoveries in rules with this eating reaction, some of which I have already posted in Misc. Discoveries in OCA.

A p2 on-off and a p4 oscillator made with a spark travelling in a loop of four dominoes:

Code: Select all

x = 12, y = 7, rule = B2cei/S14t
7bo$o6bo$o5b3ob2o2$o4b2o$o8bo$9bo!

A wire in a derivative:

Code: Select all

x = 19, y = 19, rule = B2cei/S13r4t
2ob2o2$5b2o$2bo$2bo4b2o$4bo$4bo4b2o$6bo$6bo4b2o$8bo$8bo4b2o$10bo$10bo
4b2o$12bo$12bo4b2o$14bo$14bo$16bo$16bo!

[TheWayOfTheCon]

And a second small ship (2c/4):

Code: Select all

x = 3, y = 6, rule = B2cei/S14t
bo$obo4$bo!

Here's a stable reflector for said ship. This can also eat ships depending on their phase.

Code: Select all

x = 13, y = 17, rule = B2cei/S14t
o$o$9b2o$11bo$9b2o$o$o4$o$o$10b2o$12bo$10b2o$o$o!

[rabbit]

B34w/S2-n3 is a particularly good near-Life starting point due to B-heptominoes generating a backward LWSS:

Code: Select all

x = 23, y = 4, rule = B34w/S2-n3
2o18b2o$b2o18b2o$2o19bo$o!

According to ranger, the B-heptomino works identically in rules in the range B34w/S2-n3-ck - B34ewz6ci8/S2-n34cety5ek6ei78.

Although, keeping up to the generation that the LWSS stabilizes (gen 13) gives the more permissive B3-eky4w/S2-n3-ceky - B34cekwyz5cer6ci8/S2-n34centy5cekn6ei78.

EDIT: Huge rake a few transitions away:

Code: Select all

x = 7, y = 5, rule = B34wz/S2-n3-e8
b2o$2o$b2o$5b2o$5b2o!

[NNlk05]

Reviving this thread with:
Min: B2ce3-jkqy4rt5a7c/S1c2e3ejn5y
Max: B2cei3-jqy45-ci678/S1c2-ac3ejknq4-irw5-i6-e7e8
...has three small spaceships (T, V and A)

Code: Select all

x = 15, y = 3, rule = B2ce3-jkqy4rt5a7c/S1c2e3ejn5y
12b3o$3o2bobo4bo$bo4bo5bo!

[NNlk05]

Nice rulespace with a 3-celled (2, 1)c/9 spaceship

Code: Select all

x = 3, y = 3, rule = B2-ak3jkqy4-aijkr5cnq6-ce7e/S12-ak3-jnr4cijqt5ejkry8
2o2$bo!

Min: B2ce3j/S12ce3aq4iq
Max: B2-ak3jkqy4-ijkr5-iy6-e78/S12-ak3-jnr4-aw5-q678

[ThePlayzr]

I don't know much about rulegolfing, but I think you could engineer a very cool rule based on this pattern:

Code: Select all

x = 7, y = 3, rule = B2ce3a4arty56-c/S23-ij4ir5-y
bobo$2o3bo$bob4o!

By finding a rule where it dies quicker or is some gigantic periodic puffer that is perhaps even diagonal.
Minrule:

Code: Select all

x = 7, y = 3, rule = B2c3a4ary5eij/S2aei3aer4ir5ai
bobo$2o3bo$bob4o!

Maxrule:

Code: Select all

x = 7, y = 3, rule = B2cen3aekq4-cik56-c78/S23-ij4-ak5-y6-ac78
bobo$2o3bo$bob4o!

Interesting rules will probably be closer to the minrule.
EDITED
EDIT 2: the main problem with the maxrule is that the other side of the linestretcher burns too quickly, meaning it catches up to the spaceship.
If you find an interesting variant, PM me!