#N 1-2-3-4
#C A period 4 oscillator.
#C www.conwaylife.com/wiki/index.php?title=1-2-3-4
x = 11, y = 11, rule = B3/S23
5bo5b$4bobo4b$3bobobo3b$3bo3bo3b$2obobobob2o$obo5bobo$3b5o3b2$5bo5b$4b
obo4b$5bo!