Thread for basic questions

[confocaloid]

A question: Is it possible to copyright/patent/restrict a pattern to a particular audience, or CA in general?

Interesting that you would ask that again, after an earlier discussion with some responses from various people:
viewtopic.php?p=196338#p196338

[Haycat2009]

A question: Is it possible to copyright/patent/restrict a pattern to a particular audience, or CA in general?

Interesting that you would ask that again, after an earlier discussion with some responses from various people:
viewtopic.php?p=196338#p196338

I was asking that because of a particular fiasco involving a “copyrighted” c/8c spaceship - Apparently, only moderators are legally allowed to use it.

[hotdogPi]

As a moderator, I will say that that spaceship (which wasn't even real and was just an April Fools' joke) was never copyrighted, and nobody ever claimed it was, even on April Fools' Day.

[confocaloid]

[...] that spaceship (which wasn't even real and was just an April Fools' joke) [...]

I think the top row below is what appeared to be the eight phases (when viewed in LifeViewer), and capturing that sequence of configurations as an actual evolutionary sequence in some isotropic cellular automaton remains an open problem.

It looks like dvgrn has gone to great lengths to keep the Secret Moderator Camelship a secret, but I just really think everyone should have access to this. [...]

"Phases" (top row), evolved 1 tick (middle row), XOR-pasted (bottom row):

Code: Select all

x = 478, y = 161, rule = B3/S23
350bo13bo34b2o12b2o$250bo13bo34b3o11b3o33b4o10b4o32bo2bo10bo2bo$150bo
13bo34b3o11b3o33b3o11b3o32bo2b2o9bo2b2o32bob2o10bob2o32bo3bo9bo3bo$2o
12b2o34b2o12b2o33b3o11b3o33b3o11b3o33bo2bo10bo2bo31b2o2b2o8b2o2b2o35bo
13bo32bo2bo10bo2bo32bo2b2o9bo2b2o$o2bo10bo2bo31b2o12b2o34bo2bobo8bo2bo
bo30bob2obo8bob2obo30bo2b2o9bo2b2o30b3ob2o8b3ob2o32b4o10b4o33bob2o10bo
b2o31bo2b2o9bo2b2o$o3bo9bo3bo31b2ob3o8b2ob3o33b2o12b2o31b2o2bo9b2o2bo
30bo3bo9bo3bo31bo13bo34bo4bo8bo4bo31bo3bo9bo3bo$bo2b2o9bo2b2o30b2obo
10b2obo32b2obo10b2obo32b2o12b2o34b3ob2o8b3ob2o30b3o2bo8b3o2bo30b2o12b
2o36bobo11bobo31b3ob3o7b3ob3o$bo2b2o9bo2b2o34b2o12b2o30b2ob2o9b2ob2o
34bob2o10bob2o33b2o12b2o35bo13bo33bob2o10bob2o29b2obob3o6b2obob3o29bo
5b2o6bo5b2o$51bobo11bobo33bobob3o7bobob3o33b4o10b4o29b2o4bo7b2o4bo27b
4obo2b2o4b4obo2b2o25bo2b2ob2ob2o3bo2b2ob2ob2o28b2ob3obo6b2ob3obo25b3ob
obo7b3obobo$b3ob3o7b3ob3o29b3o2b3o6b3o2b3o27b2ob2o2b2o5b2ob2o2b2o27b2o
b2o3bo5b2ob2o3bo26b3o2bo3b2o3b3o2bo3b2o25b3o2b2o2b2o3b3o2b2o2b2o25bo3b
o8bo4bo30b2o3bo3bobo2b2o3bo3bobo25bobo5bob2o2bobo5bob2o$2bo5b2o6bo5b2o
26bo3bo3bo5bo3bo3bo27bo5bo7bo5bo28b2o5bobo4b2o5bobo26bo2bo2b2obo3bo3bo
2b2obo26bobo3b2ob2ob2ob2o3b2ob2o25bobo2b3o4bo3bo2b3o29bob5o2bo4bob5o2b
o25bo2b2obo3bo3bo2b2obo3bo$3obobo7b3obobo29bobo4b2obo3bobo4b2obo25bo6b
o2b2o2bo6bo2b2o24b2o4b2o3b2ob2o4b2o34b2o3b2o7b2o36bo2b2o9bo29bo2bo2bo
3b2ob2o2bo2b2o31bob2o10bob2o28b2o4b2o6b2o4b2o$obo5bob2o2bobo5bob2o23b
2obobo2bob3ob2obobo2bob3o23b2o5bo5b3o5bo28b3o8bo3b2o8b2o23bo3bo2b2o2bo
6bo2b2o30b2o2b2o2bo5b2o2b2o28b4o3bo6b4o3bo28bo2b3obo6bo2b3obo31bo13bo$
o2b2obo3bo3bo2b2obo3bo29bo2b2ob2o6bo2b2ob2o25bo2b4o3b2o2bo2b4o3bo25b4o
2bo3b2o2b4o2bo27bo2b2o7bobo2b2o31b3o2bo7b4o2bo31b2o2bob2o5b3o2bob2o27b
o4bob2o5bo4bob2o27b2o6bo5b2o6bo$2b2o4b2o6b2o4b2o28bo2bo3bo6bo2bo3bo27b
2obo2bo7b2obo2bo28bo6bo6bo6bo28bob2o2b2o5b2ob2o2b2o31bo3bo9bo3bo28b4o
8bob4o32bo3b3o7bo3b3o32b2obobo8b2obobo$4bo13bo32b3o4b2o5b3o4b2o27b3obo
2b2o5b3obo2b2o26bo6b2o5bo6b2o26b3o6bo4b3o6bo29bo3bo5bo3bo3bo31b2o2bobo
2bo4b2o2bobo30bo4b2o7bo4b2o26bo5bob3o3bo5bob3o$2o6bo5b2o6bo31b2o2bo9b
2o2bo27bo2b4o7bo2b4o29bo5b2o2bo3bo5b2o2bo24b2o5bo3bo2b2o5bo3bo23bo3bo
4b2obobo3bo4b2ob2o31b3o11b3o26b6o3b2o3b6o3b2o25b2o3bo2bo2bo2b2o3bo2bo
2bo$4b2obobo8b2obobo26b2o4b2obo4b2o4b2obo26b3obo2bob2o3b3obo2bob2o25b
3o4bob2o3b3o4bob2o24b2ob2o3bob2o2b2ob2o3bob3o29bobo2bo5b2obobo2b2o23b
3o2b2obo2bob4o2b2obo2b2o23bobo2b2o4b2obobo2b2o4b2o23bo5b2obo4bo5b2o2b
3o$bo5bob3o3bo5bob3o25b2o2bobobobo3b2o2bobobobo29bobobo9bobobo26bob2o
2bo2bob4ob2o2bo2bobo24bo4b2ob2o4bobo2b2ob2obo23b3o2b2o2bo2bob3o2b2o2b
5o23b2o2b2ob2o4b3o2b2ob2o2bo23bo2b2o3bob2ob2o2b2o3bo28bobo2bo3bo3b2obo
2bo4b3o$b2o3bo2bo2bo2b2o3bo2bo2bo23b3o3bo2bobo2b3o3bo2bo2bo23bobo8b3o
2bo6bob2o25b4o4b2obo4b2obobobo29b2o3b2o3b3ob2o5bo24bo2bo2bob4o2b4o2bo
3b2o24bo2bo2bobo5bo2bo2bob4o23b2ob2o6b2o2b4o6b2o25bob2o2b2o6bob2o6bo$o
5b2obo4bo5b2o2b3o23bo4b6o2b2o4b3o2bo2bo22bob2ob2o4bobo3bob3ob2ob2o24bo
2bo13b2ob2o3bo23b2o2bo5b2o6bo6bo28bobo2bobo2b5obo34b2o4b2o2bo3b2ob2o
29bobo2bobo2bo4bo5bo26bo3b4o3b2obo2b2o3b3o$bobo2bo3bo3b2obo2bo4b3o24bo
bo3bobo3b3obo5bobo26b2o3bob2ob6o6bo25bo3bobo5b3o3b2o4bo31b2o3bo3bo4b2o
35b2o2bob3o5bo33bob3ob6o2b3o30bob2ob4obob4o5bo28bo9bobobo2bo2bo$3bob2o
2b2o6bob2o6bo25bob2o4bo5bobo8bo23b2o4bob2o5bo7bo31b2ob3o43b3obo6bo2b3o
33bobo2bo4b2o2bo2bo30bobobob3o5b2o2b2o29b3obob2ob2obo2b3o32bo3bo4b2o3b
o5bo$3bo3b4o3b2obo2b2o3b3o25bob4obo3b2obo3bo3bo26b2o4bo6bobo3bo32bo3bo
bo4bobo3bobobo27bo6bo5bo4bobo32bobo2bo8bo2bo32bobo2b2o4bo4b2o31b2ob3o
7bo3b2o31b3o4b3o2bo4bo$4bo9bobobo2bo2bo28b2o2bo8bob4o2bo28bo5bo5b2o4b
5o26b3o3b2o5bo2bo2bob2o27bo2bo2bo3bo9bo2bo26b2o3b2ob2o3bobo3b2o33bo3b
2o45bobo3bo2b3o40bo2b2o9bo$4bo3bo4b2o3bo5bo30bo2bo9b2o3b2o29bobo2bo7b
2o3bo2bo29b3ob2o5b2o7bo27b2o3b3o4b3o3bo3bo29bo2b2o5bobo3bobo28bo3bo3b
3ob2ob2o2bo38bo3bo7bo37bo3bo6bo$6b3o4b3o2bo4bo33b3o2bo2bo7b2o31b2obo2b
2o8bo32b3obo12bobo29bo10bobo3b3o29b2o3bo6bobo3b2o31bobob6o7bobo33bobo
3b2o5b2o36b3o2bo6bo$10bo2b2o9bo32bo4b2o9bo33bob2o12b2o31b2ob2obobo7b2o
98bo38bo9b2o35bo2bo9b2o47b3o$11bo3bo6bo36bob3obo47b2o7bo35b3o11b2o37bo
97bo$9b3o2bo6bo38b2o9bobo35bo11bo38bo10bo40bo8bo38bobo49bo48bo50bo$21b
3o36bo10b2o37b2o9bobo36bo9b2o38b3o7bo40b2o7bobo37bobo7bo41b2o7bo41bo6b
o$72bo48b2o48b2o47b3o38bo8b2o39b2o7bobo38b2o6b2o40b3o5bo$13bo257bo48b
2o48b2o47b3o$14bo6bo40bobo49bo48bo50bo$12b3o5bo42b2o5bobo39bobo5bo43b
2o5bo43bo4bo42bobo49bo48bo50bo$20b3o40bo6b2o41b2o5bobo40b2o4b2o42b3o3b
o44b2o3bobo41bobo3bo45b2o3bo45bo2bo$71bo48b2o48b2o47b3o42bo4b2o43b2o3b
obo42b2o2b2o44b3obo$16bo253bo48b2o48b2o47b3o$17bo2bo44bob2o48b2o$15b3o
bo46b2obobo43bo50bobo$19b3o44bob3o45bobo2bo$70bo49bo19$350bo13bo34b2o
12b2o34b2o12b2o$250bo13bo34b3o11b3o33b4o10b4o32bo2bo10bo2bo31b2o12b2o$
150bo13bo34b3o11b3o33b3o11b3o32bo2b2o9bo2b2o32bob2o10bob2o32bo3bo9bo3b
o31b2ob3o8b2ob3o$50b2o12b2o33b3o11b3o33b3o11b3o33bo2bo10bo2bo31b2o2b2o
8b2o2b2o35bo13bo32bo2bo10bo2bo32bo2b2o9bo2b2o30b2obo10b2obo$49b2o12b2o
34bo2bobo8bo2bobo30bob2obo8bob2obo30bo2b2o9bo2b2o30b3ob2o8b3ob2o32b4o
10b4o33bob2o10bob2o31bo2b2o9bo2b2o34b2o12b2o$50b2ob3o8b2ob3o33b2o12b2o
31b2o2bo9b2o2bo30bo3bo9bo3bo31bo13bo34bo4bo8bo4bo31bo3bo9bo3bo82bobo
11bobo$50b2obo10b2obo32b2obo10b2obo32b2o12b2o34b3ob2o8b3ob2o30b3o2bo8b
3o2bo30b2o12b2o36bobo11bobo31b3ob3o7b3ob3o29b3o2b3o6b3o2b3o$54b2o12b2o
30b2ob2o9b2ob2o34bob2o10bob2o33b2o12b2o35bo13bo33bob2o10bob2o29b2obob
3o6b2obob3o29bo5b2o6bo5b2o26bo3bo3bo5bo3bo3bo$51bobo11bobo33bobob3o7bo
bob3o33b4o10b4o29b2o4bo7b2o4bo27b4obo2b2o4b4obo2b2o25bo2b2ob2ob2o3bo2b
2ob2ob2o28b2ob3o8b2ob3o27b3obobo7b3obobo29bobo4b2obo3bobo4b2obo$51b3o
2b3o6b3o2b3o27b2ob2o2b2o5b2ob2o2b2o27b2ob2o3bo5b2ob2o3bo26b3o2bo3b2o3b
3o2bo3b2o25b3o2b2o2b2o3b3o2b2o2b2o25bo3bo8bo4bo6bo23b2o3bo3bo4bo4bo3bo
27bobo5bob2o2bobo5bob2o23b2obobo2bob3ob2obobo2bob3o$50bo3bo3bo5bo3bo3b
o27bo5bo7bo5bo28b2o5bobo4b2o5bobo26bo2bo2b2obo3bo3bo2b2obo26bobo3b2ob
2ob2ob2o3b2ob2o25bobo2b3o4bo3bo2b3o29bob5o4bob3ob4o28bo2b2obo3bo3bo2b
2obo3bo29bo2b2ob2o6bo2b2ob2o$50bobo4b2obo3bobo4b2obo25bo6bo2b2o2bo6bo
2b2o24b2o4b2o3b2ob2o4b2o34b2o3b2o7b2o36bo2b2o9bo29bo2bo2bo3b2ob2o2bo2b
2o31bobo4b2o5bob2o28b2o4b2o6b2o4b2o28bo2bo3bo6bo2bo3bo$49b2obobo2bob3o
b2obobo2bob3o23b2o5bo5b3o5bo28b3o8bo3b2o8b2o23bo3bo2b2o2bo6bo2b2o30b2o
2b2o2bo5b2o2b2o28b4o3bo6b4o3bo28bo2b3ob2o3bo4b3obo31bo13bo32b3o4b2o5b
3o4b2o$54bo2b2ob2o6bo2b2ob2o25bo2b4o3b2o2bo2b4o3bo25b4o2bo3b2o2b4o2bo
27bo2b2o7bobo2b2o31b3o2bo7b4o2bo31b2o2bob2o5b3o2bob2o27bo4bob2o10bob2o
27b2o6bo5b2o6bo31b2o2bo9b2o2bo$52bo2bo3bo6bo2bo3bo27b2obo2bo7b2obo2bo
28bo6bo6bo6bo28bob2o2b2o5b2ob2o2b2o31bo3bo9bo3bo28b4o8bob4o32bo3b3o5bo
5b3o32b2obobo8b2obobo26b2o4b2obo4b2o4b2obo$51b3o4b2o5b3o4b2o27b3obo2b
2o5b3obo2b2o26bo6b2o5bo6b2o26b3o6bo4b3o6bo29bo3bo5bo3bo3bo31b2o2bobo2b
o4b2o2bobo30bo4b2o7bo4b2o26bo5bob3o3bo5bob3o25b2o2bobobobo3b2o2bobobob
o$54b2o2bo9b2o2bo27bo2b4o7bo2b4o29bo5b2o2bo3bo5b2o2bo24b2o5bo3bo2b2o5b
o3bo23bo3bo4b2obobo3bo4b2ob2o31b3o5b2o4b5o24b6o3b11o3b2o25b2o3bo2bo2bo
2b2o3bo2bo2bo23b3o3bo2bobo2b3o3bo2bo2bo$50b2o4b2obo4b2o4b2obo26b3obo2b
ob2o3b3obo2bob2o25b3o4bob2o3b3o4bob2o24b2ob2o3bobo2bo3b2o3bobobo29bobo
2bo5b2obobo3bo23b3o2b2obo2bob3ob2obobo27bobo2b2o6bo2bo2b2o4b2o23bo5b2o
bo4bo5b2o2b3o23bo4b6o2b2o4b3o2bo$51b2o2bobobobo3b2o2bobobobo29bobobo9b
obobo26bob2o2bo2bob4ob2o2bo2bobo24bo4b2ob2o6b6obobo23b3o2b2o2bo2bob2o
4bo2b2ob2o23b2o2b2ob2o4b2o4bob3o25bo2b2o3bobo2bo3b2o3bo27bo5bo3bo3bo5b
o4bobo24bobo3bobo3b3obo5bo2bo$50b3o3bo2bobo2b3o3bo2bo2bo23bobo8b3o2bo
6bob2o25b4o4b2obo4b2obobob3o27b2o3b2ob2o2b2o2bobo2bo24bo2bo2bob4o2b3o
3bo3b2o24bo2bo2bobo11bobo2bo23b2o2bo7bo2b4o7bo23b2o2b2o2b2o4b2o2bo6b2o
25bob2o4bo5bobo8bo$50bo4b6o2b2o4b3o2bo25bob2ob2o4bobo3bob3ob2ob2o24bo
2bo13b2ob2o3bo23b2o2bo6b2o8b2o2bo28bobo2bobo2bob3obo34b2o4bo6b4o32b2o
3b3o6bo32bo3b4o3b2o4bo4b3o25bob4obo3b2obo3bo3b3o$52bobo3bobo3b3obo5bo
2bo25b2o3bob2ob6o6bobo23bo3bobo5b3o3b2o4bo31b2o2b4o4b3o36b2o2bo9bo33bo
b3ob3o4b4o33bobobo3b5o5bo28bo9bob3o2bo31b2o2bo8bob4o2bobo$53bob2o4bo5b
obo8bo23b2o4bob2o5bo7bo31b2ob3o43b3ob4ob2o3bo3bo31bobo2bo4b2o2bo2bo34b
ob3o3b2o3b3o32bobo5b2o2b3o32bo8b2obo7bo30bo2bo9b2o3b2o$53bob4obo3b2obo
3bo3b3o24b2o4bo6bobo3bo32bo3bobo4bobo3bobobo28bo5bo5bo6bo32bobo2bo8bo
2bo32bobo2b2o4bo2bo2bo32bo11bo3b2o31bo5b4obo39b3o2bo2bo7b2o$53b2o2bo8b
ob4o2bobo26bo5bo5b2o4b5o26b3o3b2o5bo2bo2bob3o27b2obo8bo2bo4bobo26bo5bo
b2o3bobo3b2obo31bo3b2o8b2obo31b2o2bo3bo2b3o3bo33b2o9b2o3b2o32bo4b2o9bo
$55bo2bo9b2o3b2o29bobo2bo7b2o3bo2bo29b3ob2o5b2o7bo27bo6bo5b2o4bo2bo27b
3o2b2o5bobo3bob2o27bo7bo3b2ob2obo2bo32bo7bo7bo36b2o3b2obo3bo36bob3obo$
57b3o2bo2bo7b2o31b2obo2b2o8bo32b3obo12bobo36bo10bobo28b2o4bo5bobo3b2o
31bo3b2o11bobo31bobobo3b2o5b2o36b3o2b2o5bo38b2o9bobo$57bo4b2o9bo33bob
2o12b2o31b2ob2obobo7b2o31bo5bo9bo2bo47bo48b2o35bo2bo9b2o35bo11b3o36bo
10b2o$59bob3obo47b2o7bo35b3o11b2o33b2o12bobo247bo$60b2o9bobo35bo11bo
38bo10bo38b2o8b2o38bobo49bo48bo50bo$60bo10b2o37b2o9bobo36bo9b2o48bo40b
2o7bobo37bobo7bo41b2o7bo41bo6bo40bobo$72bo48b2o48b2o47b3o38bo8b2o39b2o
7bobo38b2o6b2o40b3o5bo42b2o5bobo$271bo48b2o48b2o47b3o40bo6b2o$62bobo
49bo48bo50bo255bo$63b2o5bobo39bobo5bo43b2o5bo43bo4bo42bobo49bo48bo50bo
$63bo6b2o41b2o5bobo40b2o4b2o42b3o3bo44b2o3bobo41bobo3bo45b2o3bo45bo2bo
44bob2o$71bo48b2o48b2o47b3o42bo4b2o43b2o3bobo42b2o2b2o44b3obo46b2obobo
$270bo48b2o48b2o47b3o44bob3o$65bob2o48b2o350bo$66b2obobo43bo50bobo$66b
ob3o45bobo2bo$70bo49bo19$449b2o12b2o$448b2o12b2o$449b2ob3o8b2ob3o$2o
12b2o433b2obo10b2obo$o2bo10bo2bo435b2o12b2o$o3bo9bo3bo431bobo11bobo$bo
2b2o9bo2b2o430b3o2b3o6b3o2b3o$bo2b2o9bo2b2o429bo3bo3bo5bo3bo3bo$359bo
13bo75bobo4b2obo3bobo4b2obo$b3ob3o7b3ob3o302bo34bo3bo9bo74b2obobo2bob
3ob2obobo2bob3o$2bo5b2o6bo5b2o335bobobob2o6bo79bo2b2ob2o6bo2b2ob2o$3ob
obo7b3obobo337bo3b2o87bo2bo3bo6bo2bo3bo$obo5bob2o2bobo5bob2o332bo3bobo
85b3o4b2o5b3o4b2o$o2b2obo3bo3bo2b2obo3bo338bo89b2o2bo9b2o2bo$2b2o4b2o
6b2o4b2o338bobo84b2o4b2obo4b2o4b2obo$4bo13bo431b2o2bobobobo3b2o2bobobo
bo$2o6bo5b2o6bo292b2o7b2o35b3o85b3o3bo2bobo2b3o3bo2bo2bo$4b2obobo8b2ob
obo186bob3o9bo49bo40b4o5b2o34b4o85bo4b6o2b2o4b3o2bo$bo5bob3o3bo5bob3o
188bo2b2o2b2o42bo2bo5bo40bo2bo4bobo34bo2bo35b2obo11bobo8bo25bobo3bobo
3b3obo5bo2bo$b2o3bo2bo2bo2b2o3bo2bo2bo149b2o35b4ob4obo44bo46bo2bo5b2o
27bo7bo13bo24b3o11b3o2bo5bo26bob2o4bo5bobo8bo$o5b2obo4bo5b2o2b3o50bo
133bobo5bo2b2o42bo46bo2bo2bo2b3o29b2o3b2obobo10bo40bo3bo31bob4obo3b2ob
o3bo3b3o$bobo2bo3bo3b2obo2bo4b3o48b2o49bo83bob2obo2b2obo41b3o48b3obo
33bobo3bobob2o51bo6bo28b2o2bo8bob4o2bobo$3bob2o2b2o6bob2o6bo183b3ob3o
3b2obo79bobo9b4obo31b8ob3o42bo7bobo36bo2bo9b2o3b2o$3bo3b4o3b2obo2b2o3b
3o48b2o125b2o16bo98bobo32bo2b3o45b2o3bo4b2o4bo33b3o2bo2bo7b2o$4bo9bobo
bo2bo2bo51bo98bo26b5obo3bo2bo2bo3b2o29bo3bo16bo45b2obo31b3o14bo33b2obo
2b2o3b2o3bo33bo4b2o9bo$4bo3bo4b2o3bo5bo179bo3b2o5bo5b2o30b2o19bo31bo4b
2o7b2obo32bo3bo48bo5bobo40bob3obo$6b3o4b3o2bo4bo180bo6bo3bobo3bob2o33b
2o46bo3b4o41bo58bo44b2o9bobo$10bo2b2o9bo180bo5bo9bo2bo86bo96bo50bo10b
2o$11bo3bo6bo184b2o2bo9bobo85bo161bo$9b3o2bo6bo188b3o7bo$21b3o186b3o
248bobo$462b2o5bobo$13bo448bo6b2o$14bo6bo448bo$12b3o5bo$20b3o441bob2o$
465b2obobo$16bo448bob3o$17bo2bo448bo$15b3obo$19b3o!

[b-engine]

Is there any still lifes that have predecessors but not glider synthesizable?

[HartmutHolzwart]

Is there any still lifes that have predecessors but not glider synthesizable?

Still lifes always have at least one predecessor, themselves. Those proven non glider synthesizable all have essentially just themselves as predecessors.

It’s an open question to find a provably non-glider-synthesizable still life with ample predecessors.

[dvgrn]

It’s an open question to find a provably non-glider-synthesizable still life with ample predecessors.

"Ample predecessors" is a little bit difficult to define or explain.

It's easy to take, let's say, the population-154 unsynthesizable still life and add as many synthesizable sections as you want around the edges, connected to the self-forcing patch. You still end up with an unsynthesizable core, but there are lots of distinct predecessors for the non-core area, and that area can be as big a percentage of the whole still life as you want.

But as soon as you try bolting on conditions that exclude an unsynthesizable core ... e.g.,

is there a still life with N ON cells, such that it has a predecessor where all N of those cells is OFF, and yet it's not synthesizable by gliders?

... then we currently seem to be a long way from either being able to display a provably non-synthesizable still life that has no self-forcing core -- and equally far from being able to show that no such example can exist.

See, e.g., the Hypothetical FSM Still Life and the Slow High-Period Self-Forcing Agarship for examples of the kind of thing that you'd have to either build, or rigorously prove to be nonexistent, to make any progress on this question.

[muzik]

Is the block the only oscillator in B3/S23 in which every cell within the bounding box is on at least once for the evolution cycle?

Certainly there are OCA examples with periods >1, but I can't remember any that exist in Life.

Code: Select all

x = 7, y = 5, rule = B2in3/S123a
bo$o4bo$bo3bo$bo4bo$5bo!

[dvgrn]

Is the block the only oscillator in B3/S23 in which every cell within the bounding box is on at least once for the evolution cycle?

I don't think any are known. We could engineer one, if there's some way to construct a corner-spark seed that will reach all the way to the corners of the bounding box without spilling outside the bounding box. Is there any way to do that?

(I remember hunting for something along those lines -- but if I found anything, it seems like it wasn't very memorable.)

[rabbit]

A pattern that produces p-sparks at its corners might be the way. Consider this pattern:

Code: Select all

x = 9, y = 7, rule = LifeHistory
3.2B$3.4B$.2B2A3B$2B2ABA2B$.4B.2AB$3.2B3AB$5.4B!

At generation 8 it touches the corner cell and retracts, and it's easier to make a p-spark than an obo! spark.

Perhaps an edgy-LWSS+G / edgy-HWSS+G stream creating p-sparks that fills most of the bounding box with sparky retracting oscillators filling the rest.

[dvgrn]

A pattern that produces p-sparks at its corners might be the way. Consider this pattern...

Yup, it looks like there will be something constructible that works.

To clarify my claim that this is a problem that's solvable by unreasonable engineering -- I'm thinking that a self-constructing 90-degree RRO could be designed to have the every-cell-in-bounding-box-turns-ON property. An RFO would work, too, but it would have to do the P-spark trick in two corners instead of just one.

Along with constructing its child circuitry and destroying its parent copy, the RRO could reach out ahead of itself and build a very high-period countdown clock, which would run a simple construction arm that would carefully trace out a quarter of the RRO's bounding square (or a little more). When that mechanism completed its task and self-destructed, it would send a message back to the child circuitry to start the next cycle.

[hotcrystal0]

When was the last time someone used LifeCA?

[dvgrn]

When was the last time someone used LifeCA?

It looks like Scorbie reported Sokwe's true p28 glider gun to LifeCA on December 15, 2020 -- but when I tried to add a small clarification on December 17th, it bounced back with

"Your message wasn't delivered to [email protected] because the domain yahoogroups.com couldn't be found."

That brackets the final demise of Yahoo! Groups fairly well, I think.

[otismo]

I was trying to identify this SpaceShip on Life Wiki but I could not find the page that has static images -

is there one ?

Code: Select all

x = 23, y = 9, rule = B3/S23
7b3o3b3o$7bo2bobo2bo$6bo3bobo3bo$2bo6bo3bo6bo$b3o5b2ob2o5b3o$o2b2o13b
2o2bo$o3bo2bo2bobo2bo2bo3bo$b8obobob8o$3bo3bobo3bobo3bo!

interesting previous post on disappearing domain...

was thinking about resurrecting George Maydewell's Collideoscope

when you typed in the domain, all this splendid CA jumped immediately in your face

one did not click away because the site forced one to search out [ whatever ]

with LifeViewer and PatMan a site with a big "gotchya" HomePage has to be possible

it would be great if we had a collaborative effort to create such a "sticky" extravaganza -

maybe even G.M. might lend a hand...

EDIT

I want to name the SpaceShip Sparkler ( if it does not already have a name... )

the SpaceShip was from this Charity Engine Soup

Code: Select all

x = 31, y = 31, rule = B3/S23
ob2o2bo2b2o9b2o2bo2b2obo$obo2bobo2b3ob3ob3o2bobo2bobo$obob2o2bobo2b5o
2bobo2b2obobo$o2bob4obob3ob3obob4obo2bo$2ob3o3bob2o5b2obo3b3ob2o$4bob
2obob9obob2obo$2bo3bo2bob3o3b3obo2bo3bo$obob2obobobo7bobobob2obobo$b2o
bob5obo2bo2bob5obob2o$o2bo3bob2o4bo4b2obo3bo2bo$2o5bob2o3b3o3b2obo5b2o
$3o6b4obobob4o6b3o$ob2ob6o2b2ob2o2b6ob2obo$3o5bobo2bo3bo2bobo5b3o$bobo
b2o2b2o4bo4b2o2b2obobo$6b2obo3bo3bo3bob2o$bobob2o2b2o4bo4b2o2b2obobo$
3o5bobo2bo3bo2bobo5b3o$ob2ob6o2b2ob2o2b6ob2obo$3o6b4obobob4o6b3o$2o5bo
b2o3b3o3b2obo5b2o$o2bo3bob2o4bo4b2obo3bo2bo$b2obob5obo2bo2bob5obob2o$o
bob2obobobo7bobobob2obobo$2bo3bo2bob3o3b3obo2bo3bo$4bob2obob9obob2obo$
2ob3o3bob2o5b2obo3b3ob2o$o2bob4obob3ob3obob4obo2bo$obob2o2bobo2b5o2bob
o2b2obobo$obo2bobo2b3ob3ob3o2bobo2bobo$ob2o2bo2b2o9b2o2bo2b2obo!

my filename string

Two-4C8-Orthogonal-SpaceShips-From-SOUP-31X31-470cells-Charity-Engine

Cheers !

[dvgrn]

I was trying to identify this SpaceShip on Life Wiki but I could not find the page that has static images -

is there one ?

Code: Select all

x = 23, y = 9, rule = B3/S23
7b3o3b3o$7bo2bobo2bo$6bo3bobo3bo$2bo6bo3bo6bo$b3o5b2ob2o5b3o$o2b2o13b
2o2bo$o3bo2bo2bobo2bo2bo3bo$b8obobob8o$3bo3bobo3bobo3bo!

Not sure what you mean by "static images" -- you could hit Stop on the LifeViewer on the 58P8H4V0 page, I suppose.

It's just a two-step process to get to the LifeWiki page for this kind of thing: paste your RLE into the Catagolue object page, hit Find, and then click on the link that comes up (if the object has a known name and LifeWiki article).

was thinking about resurrecting George Maydewell's Collideoscope

George Maydwell resurfaced quite recently and was reportedly working on software again -- plus providing the occasional feature request to Chris Rowett. Notice that George's introduction specifically says "PM's welcomed."

[otismo]

I want to re-name 58P8H4V0 to Sparkler

I imagined I was a label

I was sewn in tents

I can imagine George and Chris collaborating

their results are awesome

gol.onl awaits them

[splitterrules]

When was this gun named the tamale?

I'm utterly speechless at the moment... Behold, a brand-new period-46 glider gun without any Snarks, twin-bees shuttles or Tanner's P46s:

Code: Select all

x = 30, y = 31, rule = B3/S23
13b2o$8b2o3bo2bobo$2o5b2o6b2ob3o$bo7bo11bo$bobo11b2ob3o$2b2o11b2obo2$
20b2o$20bo$18bobo$2o5b2o9b2o$2o5bobo$7bobo$8b2o4$20b2o$20bobo$20bobo5b
2o$10b2o9b2o5b2o$9bobo$9bo$8b2o2$11bob2o11b2o$9b3ob2o11bobo$8bo11bo7bo
$9b3ob2o6b2o5b2o$11bobo2bo3b2o$15b2o!

[dvgrn]

When was this gun named the tamale?

Technically, 5/22/2022 by iNoMed, but the name had been floating around Discord, basically lying in wait for a new notable oscillator discovery to apply it to, for a year or two before that.

The original source of the name appears to have been some kind of forum spam post about "how to reheat tamales", 9/1/2020 -- screenshot preserved on Discord -- and then somehow people didn't want to let the word go.

[Resu]

Are wickstretchers puffers?
Are there spaceships that are only 2 cells thick?

[PK22]

Are there spaceships that are only 2 cells thick?

Maybe - since there is likely a 1 cell thick spaceship (see this forum thread), there might be a way to change the design to incorporate a block and make the bounding box 2xN. The symmetry of the rest of the spaceship would make this difficult, though.

I don't know what the best way to make a unique design would be, but it should be easier than the 1 cell thick spaceship since it does not need to be symmetric. It will still be quite difficult, though.

[NooneAtAll3]

what's the smallest number of logic gates needed to implement cgol step?

I remember some gpu implementation doing amazing stuff, but my search came up only with this 2009 page with 35 gates

also I tried searching on this forum, but "minimal logic gates" or "minimum logic operations" and similar didn't work (and it's hard to dodge logic OCAs polluting search results)

[Resu]

Are all 1xN and 2xN patterns able to be synthesized by spaceships?

[PK22]

Maybe. There are no Gardens of Eden with a height < 4, so every 1xN or 2xN pattern must have a predecessor. Proving that they can all be synthesised by spaceships might be difficult - there are an unlimited number of unique patterns to account for. You also have to ensure all sparks die before the pattern becomes 1xN or 2xN, making it even harder.

I find it interesting that you used 'spaceships' instead of 'gliders' - is this to account for a hypothetical 1xN or 2xN pattern similar to the Hypothetical FSM still life?

[Resu]

Maybe. There are no Gardens of Eden with a height < 4, so every 1xN or 2xN pattern must have a predecessor. Proving that they can all be synthesised by spaceships might be difficult - there are an unlimited number of unique patterns to account for. You also have to ensure all sparks die before the pattern becomes 1xN or 2xN, making it even harder.

I find it interesting that you used 'spaceships' instead of 'gliders' - is this to account for a hypothetical 1xN or 2xN pattern similar to the Hypothetical FSM still life?

It was mostly because of the 1xN and 2xN spaceship projects.

[Citation needed]

Is there a list of known "XWSS-to-XWSS" turners (including gliderless ones)?