Spaceship Discussion Thread

[Moosey]

New c/10

Code: Select all

x = 28, y = 20, rule = B3/S23
22b2o$4b2o16b2o$4b2o15bo2bo$3bo2bo14b4o$3b4o13bob2obo$2bob2obo13bo2bo$
3bo2bo$20b2o2b2o$2b2o2b2o11bo6bo$bo6bo$20bo4bo$2bo4bo13bo2bo$3bo2bo15b
2o$4b2o$19b2o4b2o$b2o4b2o9bo2bo2bo2bo$o2bo2bo2bo3b2o4b2o4b2o$b2o4b2o6b
o4bo4bo$2bo4bo4bo$13b2o!

That's a pretty clever application of toadsuckers

I remember seeing people do that with dragons

[Gustone]

New c/10

Code: Select all

x = 28, y = 20, rule = B3/S23
22b2o$4b2o16b2o$4b2o15bo2bo$3bo2bo14b4o$3b4o13bob2obo$2bob2obo13bo2bo$
3bo2bo$20b2o2b2o$2b2o2b2o11bo6bo$bo6bo$20bo4bo$2bo4bo13bo2bo$3bo2bo15b
2o$4b2o$19b2o4b2o$b2o4b2o9bo2bo2bo2bo$o2bo2bo2bo3b2o4b2o4b2o$b2o4b2o6b
o4bo4bo$2bo4bo4bo$13b2o!

That's a pretty clever application of toadsuckers

I remember seeing people do that with dragons

And these guys

Code: Select all

x = 19, y = 38, rule = B3/S23
3bo$b2o$3bo$5b4o$6bo2bo$7b2o$8b2o2$6bo$4b2obob2obobo$5bo6bob2obo$5bo
11bo$5bo4b2o$4b6o$2bo$2o$2bo$8bo$8bo2bo$8bo2bo$9bo$3bo$b2o$3bo$5b6o$6b
o4b2o$6bo11bo$6bo6bob2obo$5b2obob2obobo$7bo2$9b2o$8b2o$7bo2bo$6b4o$4bo
$2b2o$4bo!

[Entity Valkyrie 2]

(3,0)/14 (3c/14) partial:

Code: Select all

x = 23, y = 44, rule = B3/S23
8bo5bo$8bo5bo$7bobo3bobo$8bo5bo$8bo5bo2$4bo13bo$3b3o11b3o$2b2ob2o9b2ob
2o$3b3o11b3o$4bo13bo2$3b3o11b3o$3b3o11b3o5$3b3o11b3o$3b3o11b3o$3bobo
11bobo$3b3o11b3o$3b3o11b3o3$3b3o11b3o$3b3o11b3o3$bo5bo7bo5bo$obo3bobo
5bobo3bobo$3bobo3bo3bo3bobo$3bobo11bobo$3bobo11bobo$obo3bobo5bobo3bobo
$o7bo5bo7bo$b7o7b7o$b2obob2o7b2obob2o$bo5bo7bo5bo$2b5o9b5o$2bo3bo9bo3b
o$o3bo3bo5bo3bo3bo$o2b3o2bo5bo2b3o2bo$2ob3ob2o5b2ob3ob2o!

[Moosey]

(3,0)/14 (3c/14) partial:

Code: Select all

x = 23, y = 44, rule = B3/S23
8bo5bo$8bo5bo$7bobo3bobo$8bo5bo$8bo5bo2$4bo13bo$3b3o11b3o$2b2ob2o9b2ob
2o$3b3o11b3o$4bo13bo2$3b3o11b3o$3b3o11b3o5$3b3o11b3o$3b3o11b3o$3bobo
11bobo$3b3o11b3o$3b3o11b3o3$3b3o11b3o$3b3o11b3o3$bo5bo7bo5bo$obo3bobo
5bobo3bobo$3bobo3bo3bo3bobo$3bobo11bobo$3bobo11bobo$obo3bobo5bobo3bobo
$o7bo5bo7bo$b7o7b7o$b2obob2o7b2obob2o$bo5bo7bo5bo$2b5o9b5o$2bo3bo9bo3b
o$o3bo3bo5bo3bo3bo$o2b3o2bo5bo2b3o2bo$2ob3ob2o5b2ob3ob2o!

Man, if we get a ship out of this...
but hey, it does match for about halfway through the partial, so who knows? It may be a good start

[praosylen]

(3,0)/14 (3c/14) partial:

Code: Select all

x = 23, y = 44, rule = B3/S23
8bo5bo$8bo5bo$7bobo3bobo$8bo5bo$8bo5bo2$4bo13bo$3b3o11b3o$2b2ob2o9b2ob
2o$3b3o11b3o$4bo13bo2$3b3o11b3o$3b3o11b3o5$3b3o11b3o$3b3o11b3o$3bobo
11bobo$3b3o11b3o$3b3o11b3o3$3b3o11b3o$3b3o11b3o3$bo5bo7bo5bo$obo3bobo
5bobo3bobo$3bobo3bo3bo3bobo$3bobo11bobo$3bobo11bobo$obo3bobo5bobo3bobo
$o7bo5bo7bo$b7o7b7o$b2obob2o7b2obob2o$bo5bo7bo5bo$2b5o9b5o$2bo3bo9bo3b
o$o3bo3bo5bo3bo3bo$o2b3o2bo5bo2b3o2bo$2ob3ob2o5b2ob3ob2o!

Man, if we get a ship out of this...
but hey, it does match for about halfway through the partial, so who knows? It may be a good start

Sort of... the problem is there's only one more row to expand it with the current symmetry, and unless something exists at that width (which I would say is unlikely, although you never know), anything wider requires a search at a lower order of symmetry, which would take some ridiculous exponential factor more time to complete at this width/period.

[Scorbie]

@EV2 @Moosey @A for Awesome
EV2 might wanted to point out that this is two **known** discoveries combined.
One is the front reaction, which I saw from the forums quite a long time ago, and the other is the 3c/14 partial.
Unfortunately it doesn't make a 3c/14 ship more likely, but it's an interesting combination indeed.

[Sokwe]

To clarify what Scorbie said, the pattern above is just the partial from this post advanced by two generations. Hopefully this may serve as a reminder of this particular problem. However, it is helpful when posting a pattern to mention how it was found or where it came from.

By the way, here is the underlying 3c/14 reaction on which this partial is based:

Code: Select all

x = 15, y = 7, rule = B3/S23
3b3o3b3o$2bo3bobo3bo$2bo3bobo3bo$2bo3bobo3bo$o2b3o3b3o2bo$o13bo$o13bo!

I'm not sure who first discovered it. It's probably been independently discovered several times.

[wildmyron]

To clarify what Scorbie said, the pattern above is just the partial from this post advanced by two generations.

... but with 2 cells missing from outside the original bounding box.

However, it is helpful when posting a pattern to mention how it was found or where it came from.

@EV2 This message is intended for you. Please read it. Please follow the advice in it.

[Entity Valkyrie 2]

To clarify what Scorbie said, the pattern above is just the partial from this post advanced by two generations.

... but with 2 cells missing from outside the original bounding box.

However, it is helpful when posting a pattern to mention how it was found or where it came from.

@EV2 This message is intended for you. Please read it. Please follow the advice in it.

Extremely sorry for not linking.

Oops, I meant this:

Code: Select all

x = 25, y = 44, rule = B3/S23
9bo5bo$9bo5bo$8bobo3bobo$9bo5bo$9bo5bo2$5bo13bo$4b3o11b3o$3b2ob2o9b2ob
2o$4b3o11b3o$5bo13bo2$4b3o11b3o$4b3o11b3o5$4b3o11b3o$4b3o11b3o$4bobo
11bobo$4b3o11b3o$4b3o11b3o3$4b3o11b3o$4b3o11b3o3$2bo5bo7bo5bo$bobo3bob
o5bobo3bobo$o3bobo3bo3bo3bobo3bo$4bobo11bobo$4bobo11bobo$bobo3bobo5bob
o3bobo$bo7bo5bo7bo$2b7o7b7o$2b2obob2o7b2obob2o$2bo5bo7bo5bo$3b5o9b5o$
3bo3bo9bo3bo$bo3bo3bo5bo3bo3bo$bo2b3o2bo5bo2b3o2bo$b2ob3ob2o5b2ob3ob2o
!

[Entity Valkyrie 2]

(13,1)/31 crawler

Code: Select all

x = 163, y = 57, rule = B3/S23
bo$obo6b3o$b2o4bo3b2o$2bo4bobo2b2o$b2o3bo5bo$7bo2b2o$7bo$15b2o$14b2o$
16bo5$35b3o$35bo$36bo4$57bo$56b2o$56bobo5$77b2o$77bobo$77bo5$98b2o$97b
2o$99bo5$118b3o$118bo$119bo4$140bo$139b2o$139bobo5$160b2o$160bobo$160b
o!

[dvgrn]

(13,1)/31 crawler

Code: Select all

x = 163, y = 57, rule = B3/S23
bo$obo6b3o$b2o4bo3b2o$2bo4bobo2b2o$b2o3bo5bo$7bo2b2o$7bo$15b2o$14b2o$
16bo5$35b3o$35bo$36bo4$57bo$56b2o$56bobo5$77b2o$77bobo$77bo5$98b2o$97b
2o$99bo5$118b3o$118bo$119bo4$140bo$139b2o$139bobo5$160b2o$160bobo$160bo!

There's a stub article on the (13,1)c/31 Pseudo-B climber, and a dedicated forum thread from several years ago.

Based on discoveries so far, it looks like it will be fairly difficult to get the necessary over-unity reactions out of this crawler, to build a self-supporting spaceship -- especially compared to the (27,1)c/72 Herschel-pair climber ((27,1)c/72 Herschel climber on the LifeWiki).

[dbell]

The "Switchwave" entry in the LifeWiki shows a row of switch engines stabilized at the ends by forward glider rakes and block eating reactions.

There is a more efficient stabilization of the switchwave that might be shown instead (or in addition). This has probably been known for a long time.

Code: Select all

#C A "switchwave" created by adding any number of switch engines in
#C between the two "wings" of the population 134 Cordership.
x = 283, y = 283
262boo$248bo9bo3b3o$248b4o5bobobbo$248bo3bo5bo3bobbo$266bo$250b3o10bob
o$264boo7boo$273boo5$274boo$274boo$273bobbo4boo$273boboo4boo$270b3o$
271boo$253boo9boobbo$253boo8bo4boo$264boboboo$266boo$257b3o$256boo$
241bobo11boobo$240booboo11boo$241boboo12bo$245bo$244bo$244bo3$233bo$
232b3o$$232b3o$233booboo$235bo13$215bobo$214booboo$215boboo$219bo$218b
o$218bo3$207bo$206b3o$$206b3o$207booboo$209bo13$189bobo$188booboo$189b
oboo$193bo$192bo$192bo3$181bo$180b3o$$180b3o$181booboo$183bo13$163bobo
$162booboo$163boboo$167bo$166bo$166bo3$155bo$154b3o$$154b3o$155booboo$
157bo13$137bobo$136booboo$137boboo$141bo$140bo$140bo3$129bo$128b3o$$
128b3o$129booboo$131bo13$111bobo$110booboo$111boboo$115bo$114bo$114bo
3$103bo$102b3o$$102b3o$103booboo$105bo13$85bobo$84booboo$85boboo$89bo$
88bo$88bo3$77bo$76b3o$$76b3o$77booboo$79bo13$59bobo$58booboo$59boboo$
63bo$62bo$62bo3$51bo$50b3o$$50b3o$51booboo$53bo13$33bobo$32booboo$33bo
boo$37bo$36bo$36bo3$25bo$24b3o$$24b3o$25booboo$27bo3$b3o$bbo$bbobbo$bb
obbo$3bobo$18boo$18boo$24bo$23b3o$bbo19booboo$bobo18bobo$bbo19bo3$4o$
oo3bo13bo$bo4bo11bobo$3boboo11bo$4bo15boo$21bo$18b3o$19boo$16bo$16boo$
16boo$6boo6boo$6boo4boo$12boobo$14boo5$14boo$14boo!

BCNU,
-dbell

[Entity Valkyrie 2]

Please update "switchwave" and also make a redirect from "Corderwave":

Code: Select all

x = 282, y = 282, rule = B3/S23
255b3o$255b3o$256bo$257b2o$258bo$257bo14b2o$272b2o3$255b2o$255b2o$256b
o$256bo15bo$255bobo15b2o5b2o$254bo16bobo6b2o$255bo2b2o11bo$256bo3bo10b
o$258b2o12b2o$258bo2$266bo3bo$266bo4bo$249bo15b2o4bo$248bobo15bo2bo$
266bo2bo$248bo2bo15bobo$250b2o20b3o$251bo22bo$273bo4$248b2o$250bo$248b
2o6$231bobo6bobo$230bo9bobo$231bo2bo6bo$233b3o5$223bo$222bobo2$222bo2b
o$224b2o$225bo5$222b2o$224bo$222b2o6$205bobo6bobo$204bo9bobo$205bo2bo
6bo$207b3o5$197bo$196bobo2$196bo2bo$198b2o$199bo5$196b2o$198bo$196b2o
6$179bobo6bobo$178bo9bobo$179bo2bo6bo$181b3o5$171bo$170bobo2$170bo2bo$
172b2o$173bo5$170b2o$172bo$170b2o6$153bobo6bobo$152bo9bobo$153bo2bo6bo
$155b3o5$145bo$144bobo2$144bo2bo$146b2o$147bo5$144b2o$146bo$144b2o6$
127bobo6bobo$126bo9bobo$127bo2bo6bo$129b3o5$119bo$118bobo2$118bo2bo$
120b2o$121bo5$118b2o$120bo$118b2o6$101bobo6bobo$100bo9bobo$101bo2bo6bo
$103b3o5$93bo$92bobo2$92bo2bo$94b2o$95bo5$92b2o$94bo$92b2o6$75bobo6bob
o$74bo9bobo$75bo2bo6bo$77b3o5$67bo$66bobo2$66bo2bo$68b2o$69bo5$66b2o$
68bo$66b2o6$49bobo6bobo$48bo9bobo$49bo2bo6bo$51b3o5$41bo$40bobo2$40bo
2bo$42b2o$43bo5$40b2o$42bo$40b2o6$23bobo6bobo$22bo9bobo$23bo2bo6bo$25b
3o3$14bo$2o7b2o2bobo$3o6b4o3bo$2obobo7bo$3b2o10bob2o$15bobo$16bo5$22bo
$20b5o$25bo2$23b3o$20bo$14b3o4b2o$5b2o5bo4bo8bo$5b2o6b2o2bo8bobo$13bo
12b2o6$13b2o$13b2o!

has 20 engines.

[Ashmage]

Is this a new spaceship?

Code: Select all

x = 19, y = 41, rule = B3/S23
9bo$8b3o2$5bobo3bobo$b3ob4ob4ob3o$o7bobo7bo$b2o3b3ob3o3b2o$6b2o3b2o$7b
2ob2o$b3obo7bob3o$obobo3bobo3bobobo$obobo2bo3bo2bobobo$bob3o7b3obo2$3b
o11bo$2b2o5bo5b2o$2b3o2b2ob2o2b3o$bo15bo$2bo2bob2ob2obo2bo$3bo2b3ob3o
2bo2$3b2o9b2o2$5bo2b3o2bo$3bobo2b3o2bobo$8bobo$5b3obob3o$3bo11bo$2b2ob
o7bob2o2$5b2ob3ob2o$5b2obobob2o$5b2obobob2o$b2o3b3ob3o3b2o$b2ob3obobob
3ob2o$b2o5bobo5b2o$3bo3bo3bo3bo$3bo3b2ob2o3bo$2b2o11b2o$3bo11bo$3bo11b
o!

[dvgrn]

Is this a new spaceship?...

Code: Select all

[209-cell bilaterally symmetric odd-symmetry c/3 orthogonal spaceship]

It's hard to know. You can see from Golly's Patterns/Life/Spaceships/c3-orthogonal.rle that there are hundreds of c/3 orthogonal spaceships with 50 live cells or less. Nobody has tried to keep an inventory of the millions of c/3 ships with 209 cells or less.

The first nine rows are the same as the first odd-symmetric c/3 spaceship found by David Bell in 1992:

Code: Select all

#C from Spaceships in Conway's Life (Part 3)
#C Article posted by David Bell, 7 Sep 1992
#C The spaceship was apparently discovered in March 1992
x = 19, y = 13, rule = B3/S23
9bo$8bobo$7bo3bo2$b2ob4o3b4ob2o$b2o4b2ob2o4b2o$o2bob3o3b3obo2bo2$8bobo
$6bobobobo$2b2obo7bob2o$2b2o4bobo4b2o$bo3b2o5b2o3bo!

That one is only 59 cells, but I think it would still be fairly hard to make an exhaustive collection of all c/3 ships up to that size.

Lots of other spaceships from 1992 have just the first two rows the same:

Code: Select all

#C sample c/3 spaceship found in an exhaustive search for c/3 ships
#C  that fit inside a 17x79 bounding box
#C David Bell, 9 May 1992
x = 17, y = 35, rule = B3/S23
8bo$7bobo$6bo3bo$7b3o2$5b2o3b2o$2b2o3bobo3b2o$2b2o3bobo3b2o$2o5bobo5b
2o$4b2obobob2o$o6bobo6bo$3b2o2bobo2b2o$bo2bobo3bobo2bo$b2o11b2o$b2o11b
2o$4bo7bo$4b3o3b3o$6bo3bo$3b2obo3bob2o$5b2o3b2o$5bobobobo2$5bo2bo2bo$
6b2ob2o$5b2o3b2o2$4bo2b3o2bo$3b11o$3b2obo3bob2o2$7b3o$3bo2b2ob2o2bo$2b
4obobob4o$bo3b2o3b2o3bo$2bo11bo!

Your spaceship is 19 cells wide instead of 17, so it wouldn't have showed up in that old 1992 search. But it's been a quarter-century-plus since then, so it might or might not have turned up in passing in somebody's c/3 search.

[Sokwe]

Is this a new spaceship?

The short answer is "no". When you post a pattern, it would also be nice if you could describe how you found it. This could be as simple as telling us what search program you used (e.g., "found with JLS").

Now here's the long answer:

Tim Coe wrote the program knightt to investigate the complete spaceship tree for spaceships of a given speed, period, width, and symmetry. A complete search with knightt gives a set of spaceships that could be used to construct any possible spaceship of the given type and width. I collected together the completed knightt results here. Your spaceship is a period-3 c/3 orthogonal spaceship with a width of 19 and bilateral symmetry. The table in the link indicates that the knightt search has been completed for this type of ship. The results are in c3/c3-w10-o.rle.gz (download and open in Golly) and your ship is in row 29, column 6.

Here are some other spaceship and moving object collections:

• jslife-moving: the most comprehensive collection of moving objects in Life.
• Lots of spaceships: a collection of gfind results compiled by Jason Summers.
• ptpuffer: a collection of c/2 orthogonal puffers by Paul Tooke.
• c/5 rakes: a collection of c/5 orthogonal rakes by Paul Tooke.

Edit:

Your spaceship is 19 cells wide instead of 17, so it wouldn't have showed up in that old 1992 search. But it's been a quarter-century-plus since then, so it might or might not have turned up in passing in somebody's c/3 search.

This ship is contained in Jason Summers' "lots of spaceships" collection (at "#P 118 286" in this file), so it has been known since October 2000 at the latest.

[Entity Valkyrie 2]

Spaceship anyone?

Code: Select all

x = 3, y = 3, rule = B3/S23
3o2$obo!
#C [[ STOP 4 ]]

[dvgrn]

Spaceship anyone?

Code: Select all

x = 3, y = 3, rule = B3/S23
3o2$obo!
#C [[ STOP 4 ]]

Sure, that's a common c/4 front end. Often shows up in pairs, like in some of these ships. Also look along the left edge of Patterns/Life/Spaceships/c4-orthogonal.rle. Did you look at known c/4 spaceships at all, before posting this?

[Hdjensofjfnen]

Spaceship anyone?

Code: Select all

x = 3, y = 3, rule = B3/S23
3o2$obo!
#C [[ STOP 4 ]]

There's a good example in one post that's just a few posts above yours:

And these guys

Code: Select all

x = 19, y = 38, rule = B3/S23
3bo$b2o$3bo$5b4o$6bo2bo$7b2o$8b2o2$6bo$4b2obob2obobo$5bo6bob2obo$5bo
11bo$5bo4b2o$4b6o$2bo$2o$2bo$8bo$8bo2bo$8bo2bo$9bo$3bo$b2o$3bo$5b6o$6b
o4b2o$6bo11bo$6bo6bob2obo$5b2obob2obobo$7bo2$9b2o$8b2o$7bo2bo$6b4o$4bo
$2b2o$4bo!

[mscibing]

Also, if one is found, it should be called scholar or something, because a weekender is a person who spends time in a certain place on weekends while a scholar spends time in a certain place on weekdays.

I think scholar is a fine name. My search program found such a friend at 8:21 this morning after 11 days of searching on a Ryzen 5 2400G.

Code: Select all

#C 383P7H2V0
#C [[ TRACK 0 -0.2857 ]]
x = 23, y = 82, rule = B3/S23
11bo$10b3o$10b3o2$6b3o5b3o2$6bobo5bobo$6bobo5bobo$7bo7bo$6bo2bo3bo2bo$
7bob2ob2obo$4bo4bo3bo4bo$4b6o3b6o$4bo4bo3bo4bo$5b2obo5bob2o$9bo3bo$5bo
11bo$5bo3bo3bo3bo$6bo2bo3bo2bo$6bo2bo3bo2bo$b3o3bobo3bobo3b3o$o2bo3b9o
3bo2bo$o2bo2b2ob5ob2o2bo2bo$7b2o2bo2b2o$6b2o3bo3b2o$6b2o7b2o$9b2ob2o$
6bo3bobo3bo$6bo3bobo3bo$6b2o2bobo2b2o$8b3ob3o$4b2ob2o5b2ob2o$3bo2b2o7b
2o2bo$2bo17bo$3bob3o7b3obo$6bo2bo3bo2bo$7b3o3b3o$4b2o4bobo4b2o$9bo3bo$
5bo4bobo4bo$2bo6b2ob2o6bo$b2o2b3obo3bob3o2b2o$o5b4o3b4o5bo$bo3b2o2bo3b
o2b2o3bo$2b3o2bobo3bobo2b3o2$7b3o3b3o$6b2o7b2o$5b2o9b2o$5bobo7bobo$6bo
9bo$7bobo3bobo$7bobo3bobo$6bo9bo$6bo9bo$6bo3bobo3bo$7bo2bobo2bo$7bo2bo
bo2bo2$8b3ob3o$8bobobobo$9b5o$3b3o11b3o$3b3o11b3o$bo3bo11bo3bo$5bo11bo
$6bo9bo$bo3bo3bobobo3bo3bo$2b2o4bo5bo4b2o$3bo15bo$4b3o9b3o$5bo5bo5bo$
10b3o$9b2ob2o$9b5o$6b3o2bo2b3o$4bo13bo$4bobo9bobo$6bo9bo$3bobo11bobo$
2bo2bo11bo2bo$3b2o13b2o!

I've upload the search script to https://gitlab.com/andrew-j-wade/life_slice_ship_search. The partial spaceship extraction isn't working 100% reliably which manifests as occasional file not found errors, but it doesn't impact the search.

The width is not necessarily minimal; I jumped straight into a width 23 odd symmetric search without trying a width 21 search first.

-- Andrew Wade

[testitemqlstudop]

Awesome work on finding the second elementary 2c/7! I think "scholar" is a fine name too. By the way, I've asked seven months ago how to configure your search script for a specific speed....

[mscibing]

By the way, I've asked seven months ago how to configure your search script for a specific speed....

Sorry... I need to clean up the user interface. It's down to the --period and --starts parameters, and for oblique spaceships the --shifts parameter as well.
The --period is self explanatory.

The program uses a transformation similar to that described in https://arxiv.org/pdf/cs/0004003.pdf, arranging the rows in all phases into a single sequence. But I punted and entered the transformation pattern directly instead of deriving it from the velocity; this pattern is the --starts parameter. The number cells forward is the period minus the number of starts so if you have a period of 7 and 5 starts coordinates the spaceship would be moving 7-5 = 2 cells every 7 generations.

For "--starts" of 0,2,3,1,6,0,1,2,4,1 the first 5 rows in the search would be:

Code: Select all

3...
....  ^
.5..  | time
.2..  |
....
..4.
..1.  <-- head  tail -->

And then the pattern will repeat one cell towards the tail and one generation in the past, wrapping around with the period:

Code: Select all

36..
.8..  ^
.5..  | time
.2a.  |
..7.
..4.
..19  <-- head  tail -->

Starts like the following would also work okay with my program (I'm not sure this is true of gfind), but would probably result in a slower search than the previous pattern:

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....
....  ^
..5.  | time
..4.  |
..3.
..2.
..1.  <-- head  tail -->

[testitemqlstudop]

Okay, I've set up a 3c/8 odd search using the same starts as the 2c/7 odd search. What do the numbers printed by the program represent?

EDIT: It crashed with

Code: Select all

0147/09
error: Os { code: 2, kind: NotFound, message: "No such file or directory" }
0147/10
error: Os { code: 2, kind: NotFound, message: "No such file or directory" }

What does this mean?

[Sokwe]

I am once again impressed with the speed of your program! 11 days for a width-23 symmetric search to that depth seems incredibly fast! Since you hadn't given an update on the forums in almost a year and a half, I thought you might have dropped this project. I am relieved to see that you have been working on it all this time.

I am struck by the addition of "scripts to find weekender and spaghetti monster". Spaghetti monster is difficult to find even if you know it's there. I am wondering how much of the spaghetti monster structure you start with in order to find the complete ship, and how quickly does it find it?

Also, your post in the sandbox would have been better suited for the spaceship discussion thread. It is always helpful to see long, new partial results for high-period searches.

Edit: Please answer the following questions in this thread in the scripts forum. When I get a reply, I will also move some of the above posts from here to there.

For "--starts" of 0,2,3,1,6,0,1,2,4,1 the first 5 rows in the search would be:

Code: Select all

3...
....  ^
.5..  | time
.2..  |
....
..4.
..1.  <-- head  tail -->

And then the pattern will repeat one cell towards the tail and one generation in the past, wrapping around with the period:

Code: Select all

36..
.8..  ^
.5..  | time
.2a.  |
..7.
..4.
..19  <-- head  tail -->

I'm not sure how to read your diagrams. Here is a guess:

Each point in the grid is a single complete row (in a single phase) of the partial spaceship. A row at a grid point evolves into the row at the grid point directly above it (so row 1 evolves into row 4). When you try to advance a row in the last phase, you go back to the first phase, but shift towards the tail by the number of cells forward each period (2 cells forward, so row 3 evolves into row 1).

Starts like the following would also work okay with my program (I'm not sure this is true of gfind), but would probably result in a slower search than the previous pattern:

Code: Select all

....
....  ^
..5.  | time
..4.  |
..3.
..2.
..1.  <-- head  tail -->

So would the next two iterations through the starts look like this?

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.6...
.....  ^
..5..  | time
..4a.  |
..39.
..28.
..17.  <-- head  tail -->

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.6c..
..b..  ^
..5..  | time
..4a.  |
..39f
..28e
..17d  <-- head  tail -->

And a 3c/7 search might look like this ("--starts" of 0,3, 2,2, 4,1, 6,0)?

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45....
.89...  ^
.3c...  | time
..7...  |
..2b..
...6..
...1a.  <-- head  tail -->

Will different starts still essentially cover the same search space? What advantage do you see to one choice of starts over another?

Edit 2: Oh, I forgot something: congratulations!

[Moosey]

Nice new 2c/7!
Congratulations!

EDIT: and it was discovered by Andrew J. Wade! I feel kinda honored!