#N Jam on 44P7.2
#C The smallest known non-trivial period 21 oscillator. Has a single cell that oscillates at the full period.
#C www.conwaylife.com/wiki/index.php?title=Jam_on_44P7.2
x = 17, y = 16, rule = b3/s23
3b2o7bo4b$3b2o6bobo3b$3bo7bobo3b$bob3o4b2obob2o$obobo2bo5b2obo$o2bo5bo
b2o4b$b2o9bo4b$9b3o5b$6bobo8b$4bo3bob2o5b$2b3obobob2o5b$bo4b2o9b$2b4o
11b$5bo11b$4bo12b$4b2o!