Ian07 wrote:The current cost of

xs18_0mmge96z1221 is 12 gliders, which is twice as many as anything else on the new version of the wiki's

list of common still lifes. Most of the sample soups boil down to this reaction:

`x = 20, y = 15, rule = B3/S23`

2o4bo$2o3bo3bo$4bo4bo$4b2obo2bo$4b3ob3o$8bo4$18bo$17bobo$16bo2bo$11bo

5b2o$11bo$11bo!

If a 4G synthesis is found for the unstable object, this could reduce the cost to 4 + 2 (block) + 3 (loaf+blinker) + 1 (cleanup) = 10G.

Yes, but the reason for the high frequency is this 4G pattern:

`x = 5, y = 18, rule = B3/S23`

3b2o$2bobo$3bo13$3o$2bo$3o!

Maybe a weird (early) clean up with some gliders improves the synthesis.

Edit1: an alternative

`x = 10, y = 20, rule = B3/S23`

7bo$6bobo$9bo$4bobo$3b2o2bobo$4bo$9bo4$3ob3o$o5bo$o5bo$bo3bo$2b3o$6bo$

6bo$2bo3bo$2bo$2bo!

3G (2blinkers)+2G (pi) + 3G (dove) + cleanup.

or this one:

`x = 12, y = 13, rule = B3/S23`

5bo$5bo$5bo2$7b3o2$2o$2o$9b2o$9b2o$11bo$9b2o$9b2o!

3G (2blinkers)+2G (pi) + 2G (block) + cleanup.

or this one:

`x = 25, y = 22, rule = B3/S23`

21bo$20bobo$20bo2bo$21bobo$21b3o4$19b2o$18bobo$17bobo$17b2o$10bo$10bo$

10bo2$6b3o3b3o2$10bo$10bo$10bo!

with a costly long ship.

Edit2, sorry for posting a lot, but this one seems promising:

`x = 19, y = 8, rule = B3/S23`

bo15bo$bo15bo$2bo15bo$2o14b2o$2bo2bo12bo$bo2bobo10bo$3bo2bo$4b2o!

a loaf plus a 7-bit phi-spark ancestor.