#N Switch engine ping-pong
#O Michael Simkin, 29 October 2014
#C The smallest known pattern that exhibits quadratic population
#C growth, as of June 2018.
#C www.conwaylife.com/wiki/Switch_engine_ping-pong
x = 210515, y = 183739, rule = B3/S23
1148bo$1148b2o1076$145bo$144bo$144b3o158$3bo$b2o$o$bo182353$210513bo$
210512bo$210512b3o141$210354bo$210353b3o$210355bo!