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Golly
Golly is a free program that allows you to easily explore much larger patterns at higher speeds than any web-based applet ever could.
October 15th, 2016

A week or so ago, a better recipe was found for the last still life on Mark Niemiec's list of expensive 14-bit syntheses. Now all 14-bit still lifes can be constructed with less than 14 gliders -- less than 1 glider per bit, as the old saying goes.

Catagolue results continue to be very useful in finding new recipes.


Code: Select all
#C 12-glider synthesis for the last 14-bit still life,
#C snake bridge snake / 12.105, which had previously cost at least
#C one glider per bit.
#C Goldtiger997, 6 October 2016, optimized by Mark Niemiec on 7 October.
x = 79, y = 71, rule = LifeHistory
7.A$.A6.A$2.A3.3A$3A2$16.A$14.A.A$15.2A6$36.A$34.A.A$35.2A8$30.3A$32.
A$31.A4$31.3A$33.A11.2D.D$32.A12.D.2D$43.2D$39.2D.D$39.D.2D6$52.A$51.
2A$20.2A5.3A21.A.A$21.2A6.A$20.A7.A22$3.3A$5.A70.2A$4.A4.2A65.A.A$10.
2A64.A$9.A!
#C [[ AUTOFIT AUTOSTART GPS 25 LOOP 150 ]]

UPDATE: The next challenge along these lines was to similarly reduce 15-bit still life costs to below 1 glider per bit. The process started later in the same forum thread, and was completed on November 19, 2016, with the following 14-glider synthesis:

Code: Select all
#C 14-glider synthesis for the last 15-bit still life
#C which had previously cost at least one glider per bit.
#C Extrementhusiast, 19 November 2016
x = 48, y = 38, rule = B3/S23
17bobo$17b2o$18bo$4bobo$5b2o$5bo$18bo$18bobo$18b2o2$obo$b2o39b2o$bo40b
o3b2o$20b3o21bo2bo$20bo22b2obo$21bo6bo16bo$8b2o18bobo14bobo$7bobo18b2o
16b2o$9bo2$5b2o$4bobo$6bo9b2o$10b2o3bobo$11b2o4bo$10bo4$8b3o$7bo2bo$
10bo$6bo3bo$10bo$7bobo$32b3o$32bo$33bo!
#C [[ AUTOFIT AUTOSTART GPS 25 LOOP 150 ]]

Read the whole story at b3s23life.blogspot.com

 

September 8th, 2016

Take a look at a pre-loaf and a pi:screen-shot-2016-09-07-at-11-37-22-pm

If you run them in B37c/S23, the pre-loaf stabilizes quickly, but the pi takes a while — and some space. It needs 110 generations to settle down.

If you run them in B37e/S23, though, the pre-loaf just becomes a loaf immediately and the pi stabilizes much more quickly, in only 23 generations, and without spreading out so much.

Read the whole story at mathematrec.wordpress.com

 

September 4th, 2016

That lame explanation seems even more lame when you consider this: The non totalistic rule B37c/S23 (meaning birth occurs if there are 3 live neighbors, or if there are 7 live neighbors with the dead neighbor in the corner of the neighborhood) is explosive, but B37e/S23 (birth occurs if there are 3 live neighbors, or if there are 7 live neighbors with the dead neighbor on the edge of the neighborhood) isn’t.


Read the whole story at mathematrec.wordpress.com

 

September 4th, 2016

Here’s an even more perplexing (to me, at least) instance of different CA behavior under similar-but-different rules. Consider this 32 x 32 soup:Screen Shot 2016-09-04 at 10.14.02 AM B36/S23 is a Life-like rule sometimes called HighLife. Many objects behave the same way as in Life; in particular, blocks, loaves, boats, and beehives are still lifes; blinkers are p2 oscillators; gliders are c/4 diagonal spaceships. So after 378 generations in B36/S23 when that soup looks like this, it’s stabilized:Screen Shot 2016-09-04 at 10.10.26 AM B38/S23 has no nickname I know of. Under that rule, the same soup stabilizes in 483 generations:Screen Shot 2016-09-04 at 10.10.52 AM And in B37/S23… here’s what it evolves to after 10,000 generations:Screen Shot 2016-09-04 at 10.11.08 AMPopulation 17,298 and growing, presumably forever.

Fairly typical. I’ve seen some soups take several thousand generations to stabilize in B38/S23, and I’ve seen a few — very few — stabilize in B37/S23. But most soups stabilize in 1000 generations or so in B36/S23 and B38/S23… and almost all soups explode in B37/S23.

Does that make any sense to you? Explain it to me, then.

Read the whole story at mathematrec.wordpress.com

 

September 2nd, 2016

It surprises me how hard it can be to guess what kind of behavior a given CA rule will produce. There are some things that are fairly obvious. For instance, under a rule that doesn’t include births with fewer than 4 live neighbors, no pattern will never expand past its bounding box. (Any empty cell outside the bounding box will have no more than 3 live neighbors, so no births will occur there.)

But beyond a few observations like that, it’s hard to predict. At least for me.

Consider the rule B34/S456, for a semi random example. Start with a 32 by 32 soup at 50% density:gen0 Then let it run for 1000 generations. It expands to a blob 208 by 208 in size, population 21,132:b34s456But change the B34/S456 rule to B3/S456 or B4/S456 — removing one number or the other from the birth rule — and either way, the same initial configuration dies.

Read the whole story at mathematrec.wordpress.com

 

July 17th, 2016

Here’s another big spaceship evolving from a soup. The rule here is B358/S23, and the soup has D2_+1 symmetry.Screen Shot 2016-07-17 at 7.06.44 AM

x = 143, y = 41, rule = B358/S23
47b2o$49bo$51b2o$45bo7bo32bo$b2o21bo20bob3o36bo35b3o$o2bo19bobo24bo3bo
30bobo34bo14b2o$bobo18bo3bo14bobo5b2o32bo5bo32bo4bo12b2o$5bob3o12bo3bo
17b3obo2b4o2bo24bo7bo17bobo12bo12b2obo2bo$7bo2bo12bobo15bo3b2ob2o3bo3b
o25bobobobo18bobo14bo2bo4bo3bob2obo$3b5ob2o13bo15bo2b3o11b2o25bo3bo35b
2o2bo4bo3bo2b3o$2bo2bo36bo3b2o3b2o4bobo19b2o34b2o6bo4bo4bo$2bo2b2o5b2o
30bob2o8bo2bo19b2o4bobo20bobo4b2o6bo4b2o4bo2bo$6bo6b2o2bo22b3ob2o2bo7b
o27b2ob2o19bobo13bo4bo6bo$4bob2o4b2o2bo3bo23b2o2bo7bobo26b3o37bo$2bobo
12bobobo24bobobo6bo28bo39bo$2bobo4bo7bob4o25b2o$4bo3bo3b2o4b2obo26b2o$
8b3ob2o3b2obo$18bo4$18bo$8b3ob2o3b2obo$4bo3bo3b2o4b2obo26b2o$2bobo4bo
7bob4o25b2o$2bobo12bobobo24bobobo6bo28bo39bo$4bob2o4b2o2bo3bo23b2o2bo
7bobo26b3o37bo$6bo6b2o2bo22b3ob2o2bo7bo27b2ob2o19bobo13bo4bo6bo$2bo2b
2o5b2o30bob2o8bo2bo19b2o4bobo20bobo4b2o6bo4b2o4bo2bo$2bo2bo36bo3b2o3b
2o4bobo19b2o34b2o6bo4bo4bo$3b5ob2o13bo15bo2b3o11b2o25bo3bo35b2o2bo4bo
3bo2b3o$7bo2bo12bobo15bo3b2ob2o3bo3bo25bobobobo18bobo14bo2bo4bo3bob2ob
o$5bob3o12bo3bo17b3obo2b4o2bo24bo7bo17bobo12bo12b2obo2bo$bobo18bo3bo
14bobo5b2o32bo5bo32bo4bo12b2o$o2bo19bobo24bo3bo30bobo34bo14b2o$b2o21bo
20bob3o36bo35b3o$45bo7bo32bo$51b2o$49bo$47b2o!

It goes left to right (right to left in the original soup) at speed 36c/72.

Again, the way this comes about is through development of a small seed. In this case at generation 83 you get a couple of these objectsScreen Shot 2016-07-17 at 12.09.26 PMwhich in four generations recur, inverted, but with some debris.Screen Shot 2016-07-17 at 12.09.44 PMBy itself, this seed becomes a 36c/72 puffer.Screen Shot 2016-07-17 at 12.09.02 PMBut two of them, mirror images at just the right separation, have their smoke trails interact in such a way as to extinguish them, and the result is a spaceship. If you start with this pairScreen Shot 2016-07-17 at 12.24.37 PM

Read the whole story at mathematrec.wordpress.com

 

July 8th, 2016

Hot on the heels of Rich’s p16, here’s a period 18 oscillator, once again found using apgsearch. It even bears a family resemblance to the p16: D2_+1 symmetry and shuttle behavior. But… it doesn’t work in Life (B3/S23). It works in B357/S23.Screenshot - 070816 - 11:54:22

RLE:

x = 13, y = 5, rule = B357/S23
b2ob2ob2ob2ob$o4bobo4bo$5bobo5b$4bo3bo4b$3b3ob3o3b!

Read the whole story at mathematrec.wordpress.com

 

July 5th, 2016

Here’s a new period 16 oscillator:p16

The stubby wiki page says I discovered it, which is silly of course: all I did was install apgsearch and run it looking at D2_+1 soups in standard Life (B3/S23). I was asleep when it found this and woke up to find it’d been tweeted, retweeted, reported on the forum, used to make a smaller p48 gun, deemed awesome, and written up on the wiki.

 

Read the whole story at mathematrec.wordpress.com

 

June 12th, 2016

Tim Coe has found a symmetrical spaceship with a new speed, 3c/7 (left, below) after a series of searches that took a total of "one or two months". At 29 cells wide, it is the minimum width odd symmetric spaceship -- an exhaustive width 27 search was run some time ago by Paul Tooke. The author seems to have officially chosen a name of "Spaghetti Monster" for the new 3c/7 spaceship.

Matthias Merzenich has pointed out that two of these spaceships can support a known 3c/7 wave (right, below).


Code: Select all
#C 3c/7 FSM spaceship: Tim Coe, 11 June 2016
#C Period-28 3c/7 wave found by Stephen Silver on Feb. 2, 2000
x = 187, y = 139, rule = B3/S23
10bo7bo65bo7bo$8b2ob2o3b2ob2o61b2ob2o3b2ob2o$8b2ob2o3b2ob2o61b2ob2o3b
2ob2o73bo7bo$11b2o3b2o67b2o3b2o74b2ob2o3b2ob2o$7bo5b3o5bo59bo5b3o5bo
70b2ob2o3b2ob2o$7bo13bo59bo13bo73b2o3b2o$8bo11bo61bo11bo70bo5b3o5bo$9b
2o7b2o63b2o7b2o71bo13bo$6bobobobo3bobobobo57bobobobo3bobobobo69bo11bo$
6bobob2o5b2obobo57bobob2o5b2obobo70b2o7b2o$6bobo11bobo57bobo11bobo67bo
bobobo3bobobobo$164bobob2o5b2obobo$11bo5bo67bo5bo72bobo11bobo$10b2o5b
2o65b2o5b2o$8b2o9b2o61b2o9b2o74bo5bo$8bo3bo3bo3bo61bo3bo3bo3bo73b2o5b
2o$10bo2bobo2bo65bo2bobo2bo73b2o9b2o$10bobo3bobo65bobo3bobo73bo3bo3bo
3bo$9bo9bo63bo9bo74bo2bobo2bo$7bo3bo5bo3bo59bo3bo5bo3bo72bobo3bobo$6b
4o9b4o57b4o9b4o70bo9bo$4b2obo2bo7bo2bob2o53b2obo2bo7bo2bob2o66bo3bo5bo
3bo$4b2o2b3o7b3o2b2o53b2o2b3o7b3o2b2o65b4o9b4o$7bobo2bo3bo2bobo59bobo
2bo3bo2bobo66b2obo2bo7bo2bob2o$5bob3o2bo3bo2b3obo55bob3o2bo3bo2b3obo
64b2o2b3o7b3o2b2o$5bo4bo7bo4bo55bo4bo7bo4bo67bobo2bo3bo2bobo$163bob3o
2bo3bo2b3obo$6bo15bo57bo15bo66bo4bo7bo4bo$6b2obo9bob2o57b2obo9bob2o$5b
o3b2o7b2o3bo55bo3b2o7b2o3bo66bo15bo$164b2obo9bob2o$5b2o4bo5bo4b2o55b2o
4bo5bo4b2o65bo3b2o7b2o3bo2$8b2ob2o3b2ob2o61b2ob2o3b2ob2o68b2o4bo5bo4b
2o$2bo5b2o3bobo3b2o5bo49bo5b2o3bobo3b2o5bo$bob2o5bobo3bobo5b2obo47bob
2o5bobo3bobo5b2obo64b2ob2o3b2ob2o$2o2bo3b2obo5bob2o3bo2b2o45b2o2bo3b2o
bo5bob2o3bo2b2o57bo5b2o3bobo3b2o5bo$2bob2ob6o3b6ob2obo49bob2ob6o3b6ob
2obo58bob2o5bobo3bobo5b2obo$7bo2bobo3bobo2bo59bo2bobo3bobo2bo62b2o2bo
3b2obo5bob2o3bo2b2o$4bobo2bo9bo2bobo53bobo2bo9bo2bobo61bob2ob6o3b6ob2o
bo$2b3o3bo11bo3b3o49b3o3bo11bo3b3o64bo2bobo3bobo2bo$2b3obobo11bobob3o
49b3obobo11bobob3o61bobo2bo9bo2bobo$3b3o17b3o51b3o17b3o60b3o3bo11bo3b
3o$160b3obobo11bobob3o$4bo19bo53bo19bo62b3o17b3o$2b2o21b2o49b2o21b2o$b
obo21bobo47bobo21bobo60bo19bo$b3o21b3o47b3o21b3o58b2o21b2o$159bobo21bo
bo$b2o23b2o47b2o23b2o57b3o21b3o$b3o21b3o47b3o21b3o$4bo4b3o5b3o4bo53bo
4b3o5b3o4bo60b2o23b2o$9bo2bo3bo2bo63bo2bo3bo2bo65b3o21b3o$2bobo4bo9bo
4bobo49bobo4bo9bo4bobo61bo4b3o5b3o4bo$3bo7b2o3b2o7bo51bo7b2o3b2o7bo67b
o2bo3bo2bo$6b5o7b5o57b5o7b5o63bobo4bo9bo4bobo$5b4o11b4o55b4o11b4o63bo
7b2o3b2o7bo$4b2o17b2o53b2o17b2o65b5o7b5o$6bob2o9b2obo57bob2o9b2obo66b
4o11b4o$5bob2obo7bob2obo55bob2obo7bob2obo64b2o17b2o$7b5ob3ob5o59b5ob3o
b5o68bob2o9b2obo$2b3o2b2o2b2o3b2o2b2o2b3o49b3o2b2o2b2o3b2o2b2o2b3o62bo
b2obo7bob2obo$4bo2b2o2b2obob2o2b2o2bo53bo2b2o2b2obob2o2b2o2bo66b5ob3ob
5o$3bo3b2o2b3ob3o2b2o3bo51bo3b2o2b3ob3o2b2o3bo60b3o2b2o2b2o3b2o2b2o2b
3o$3bo5bobob3obobo5bo51bo5bobob3obobo5bo62bo2b2o2b2obob2o2b2o2bo$3bo3b
5o5b5o3bo51bo3b5o5b5o3bo61bo3b2o2b3ob3o2b2o3bo$4bo3b2o9b2o3bo53bo3b2o
9b2o3bo62bo5bobob3obobo5bo$11bo2bo2bo67bo2bo2bo69bo3b5o5b5o3bo$11b2o3b
2o67b2o3b2o70bo3b2o9b2o3bo$13bobo71bobo79bo2bo2bo$169b2o3b2o$8b3o7b3o
61b3o7b3o76bobo$7bo3b2o3b2o3bo59bo3b2o3b2o3bo$8bo11bo61bo11bo71b3o7b3o
$8bo4bobo4bo61bo4bobo4bo70bo3b2o3b2o3bo$7bobobo5bobobo59bobobo5bobobo
70bo11bo$7bo3bo5bo3bo59bo3bo5bo3bo70bo4bobo4bo$7b2o3bo3bo3b2o59b2o3bo
3bo3b2o69bobobo5bobobo$11bo5bo67bo5bo73bo3bo5bo3bo$9bo9bo63bo9bo71b2o
3bo3bo3b2o$9b2o7b2o63b2o7b2o75bo5bo$10bo7bo65bo7bo74bo9bo$167b2o7b2o$
168bo7bo$9b3o5b3o63b3o5b3o$9b2o7b2o63b2o7b2o$8bo3bo3bo3bo61bo3bo3bo3bo
72b3o5b3o$9bo3bobo3bo63bo3bobo3bo73b2o7b2o$13bobo71bobo76bo3bo3bo3bo$
11bo5bo67bo5bo75bo3bobo3bo$171bobo$11b3ob3o67b3ob3o77bo5bo$11b2obob2o
67b2obob2o$9bobo5bobo63bobo5bobo75b3ob3o$8bob2o5b2obo61bob2o5b2obo74b
2obob2o$8bo11bo61bo11bo72bobo5bobo$7bo2b2o5b2o2bo59bo2b2o5b2o2bo70bob
2o5b2obo$8b2o9b2o61b2o9b2o71bo11bo$7bob2o7b2obo59bob2o7b2obo69bo2b2o5b
2o2bo$9b2o7b2o63b2o7b2o72b2o9b2o$6bo15bo57bo15bo68bob2o7b2obo$6b2o3bo
5bo3b2o57b2o3bo5bo3b2o70b2o7b2o$6b3o2bo5bo2b3o57b3o2bo5bo2b3o67bo15bo$
7bo13bo59bo13bo68b2o3bo5bo3b2o$9b2ob2ob2ob2o63b2ob2ob2ob2o70b3o2bo5bo
2b3o$10bob2ob2obo65bob2ob2obo72bo13bo$9b2ob2ob2ob2o63b2ob2ob2ob2o73b2o
b2ob2ob2o$10bo7bo65bo7bo75bob2ob2obo$10bobobobobo65bobobobobo74b2ob2ob
2ob2o$10bo7bo65bo7bo75bo7bo$168bobobobobo$8bo4bobo4bo61bo4bobo4bo7bo7b
o7bo7bo41bo7bo$8bo3bo3bo3bo61bo3bo3bo3bo6b3o5b3o5b3o5b3o$7b2obo7bob2o
59b2obo7bob2o4bo2b2o3b2o2bo3bo2b2o3b2o2bo5bo7bo7bo7bo7bo4bobo4bo$8bob
2o5b2obo61bob2o5b2obo4b2o2b2o3b2o2b2ob2o2b2o3b2o2b2o3b3o5b3o5b3o5b3o6b
o3bo3bo3bo$6bob3o7b3obo57bob3o7b3obo2b2o2b3ob3o2b2ob2o2b3ob3o2b2o2bo2b
2o3b2o2bo3bo2b2o3b2o2bo4b2obo7bob2o$5bo17bo55bo17bob3o9b3ob3o9b3ob2o2b
2o3b2o2b2ob2o2b2o3b2o2b2o4bob2o5b2obo$12bo3bo69bo3bo9b2o9b2o3b2o9b2o2b
2o2b3ob3o2b2ob2o2b3ob3o2b2o2bob3o7b3obo$11bobobobo67bobobobo39b3o9b3ob
3o9b3obo17bo$7b3o3bobo3b3o59b3o3bobo3b3o36b2o9b2o3b2o9b2o9bo3bo$7b4obo
3bob4o59b4obo3bob4o73bobobobo$9b2o7b2o63b2o7b2o71b3o3bobo3b3o$7bob2o7b
2obo59bob2o7b2obo69b4obo3bob4o$6b2ob2o3bo3b2ob2o57b2ob2o3bo3b2ob2o70b
2o7b2o$5b2o2b2o2bobo2b2o2b2o55b2o2b2o2bobo2b2o2b2o67bob2o7b2obo$8b3obo
3bob3o61b3obo3bob3o69b2ob2o3bo3b2ob2o$5b5o2bo3bo2b5o55b5o2bo3bo2b5o65b
2o2b2o2bobo2b2o2b2o$4bo7b2ob2o7bo53bo7b2ob2o7bo67b3obo3bob3o$4bo3b2o3b
obo3b2o3bo53bo3b2o3bobo3b2o3bo64b5o2bo3bo2b5o$4bobo2bo3bobo3bo2bobo53b
obo2bo3bobo3bo2bobo63bo7b2ob2o7bo$11b3ob3o67b3ob3o70bo3b2o3bobo3b2o3bo
$7b3ob3ob3ob3o59b3ob3ob3ob3o66bobo2bo3bobo3bo2bobo$13b3o71b3o79b3ob3o$
13b3o71b3o75b3ob3ob3ob3o$171b3o$11bo5bo67bo5bo79b3o$11bobobobo67bobobo
bo$169bo5bo$169bobobobo!
#C [[ AUTOFIT AUTOSTART GPS 4 ]]

This is the twenty-second spaceship velocity constructed in Conway's Life -- counting each of the four infinite families of spaceships (Gemini, HBK, Demonoid, Caterloopillar) as one velocity each.

Read the whole story at b3s23life.blogspot.com

 

April 18th, 2016

The p61 gun is quite different, though it too makes use of herschel tracks. To get a better picture of what’s going on, here it is with history turned on: the blue cells are ones that were live at some point:Screen Shot 2016-04-15 at 11.45.37 PM To start with let’s zoom in to the upper right corner. You see a couple of lightweight spaceships moving west to east, and the spark on the one near the center is about to perturb a southwest-going glider:Screen Shot 2016-04-15 at 11.48.49 PM 39 generations later, and several cells to the south, this becomes an r pentomino:Screen Shot 2016-04-15 at 11.49.24 PM And another 48 generations later, quite a bit further south, it becomes a herschel.Screen Shot 2016-04-15 at 11.50.09 PMThat herschel gets sucked up into a downward conduit (purple line below). It gets converted into two parallel southwest-going gliders. marked1One of these (red line) gets bounced off a series of 90° reflectors, snarks again like the ones we saw in the p58 gun, ending up at the top where it becomes (a later version of) the glider we saw at the start, getting converted to an r pentomino. The other one (yellow line) gets kicked right by an interaction with a herschel loop (orange line). I presume this very complicated reflector is used because it can reflect one glider without messing up the parallel stream (and I’m guessing a similar loop can’t be made to work at p58, hence the different solution used in that gun?). Not quite sure. Anyway, it then gets bounced a couple more times before ending up at the top of another section of the gun, where it’ll share the other glider’s fate: getting converted by a lightweight spaceship into an r pentomino, then a herschel, to feed another herschel track.

Here’s the middle stage:marked2Again a downward track (purple) produces two parallel gliders (red and yellow). Again the yellow one gets bounced by a herschel loop to the top of a third stage for yet another r pentomino conversion. As for the red one, it bounces a bunch of times up to the top left where it runs into… something.

The third stage yet again has a downward track producing two gliders, one bounced off a loop and the other just kicked around with snark reflectors.

Read the whole story at mathematrec.wordpress.com