#C four Snark catalyst variants
#C Top: original variant by Mike Playle
#C Left: Shannon Omick (better clearance on a diagonal)
#C Right: Heinrich Koenig (better clearance on a different diagonal)
#C Bottom: Simon Ekström (better clearance on two diagonals)
x = 51, y = 52, rule = B3/S23
#C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]]
#C [[ THUMBLAUNCH THUMBSIZE 2 ZOOM 8 HEIGHT 480 THEME Book GRID GRIDMAJOR 0 STARTFROM 232 ]]
Four Snark catalyst variants: top: Mike Playle (original variant); left: Shannon Omick (better clearance on a diagonal); right: Heinrich Koenig (better clearance on a different diagonal); bottom: Simon Ekström (better clearance on two diagonals) (click above to open LifeViewer) RLE:herePlaintext:here
The base reaction was discovered by Dietrich Leithner about 1998, but it consumed another block. A catalyst that could restore the block was found with Bellman, a program for searching catalytic reactions developed by Mike Playle. Prior to that, some attempts like p4 reflector were made with periodic sparkers.
While the repeat time is 43, a continuous period-38 stream triples the period to 114, while a continuous period-41 stream quadruples the period to 164. A period-42 stream creates an extraneous honey farm, which can be deleted with a block, doubling the period to 84; this was used in a previous version of the smallest period-84 glider gun.