Wow! What a thing to have escaped notice all this time! At the rate the Online Soup Search is going, it won't run into a methuselah that good until it's tested ten or twenty times as many candidate patterns as it has processed so far.

calcyman wrote:It can be reduced to 44 cells, at least: ...

The original methuselah stabilizes at 35,201 ticks, and Calcyman's version has the side effect of cutting that down to 35,154.

34 cells in a 27x27 bounding box can produce the same final result -- the population alternates between 5818 and 5823, which is one glider less than the original 20x20 produced, but it doesn't seem to make sense to add that glider back in! The best time I can manage is 35,180 ticks, and I have to be pretty tricky to get that much:

`#C 35,180-tick methuselah with 34 ON cells`

x = 27, y = 27, rule = B3/S23

7b2o$8b2o3$16bo$16bo$11bo4bo$5b2o4b2o$4b2o$5b2o$6bo2$21b2o$12b2o7bo$

12bo2$25b2o$25bo3$10b2o$9bobo$10bo4$3o!

Or here's another 3 cells removed at the cost of 20 ticks:

`#C 35,160-tick methuselah with 31 ON cells`

x = 31, y = 27, rule = B3/S23

11b2o$12b2o3$20bo$20bo$2bo17bo$obo$3o$o3$25b2o$16b2o7bo$16bo2$29b2o$

29bo3$14b2o$13bobo$14bo4$4b3o!

It would be nice to have an methuselah scoring system so I can decide which one of these "wins". But it's been thirty years now, and I think no two people have really quite agreed on a definition yet that can unequivocally choose a winner between all these variations on survival time, bounding box, and starting population.