204p47_synthMatthias Merzenich, 10 October 2013 142-glider synthesis of extended version of pre-pulsar shuttle 47 https://conwaylife.com/wiki/Pre-pulsar_shuttle_47 https://conwaylife.com/forums/viewtopic.php?p=9330#p9330 https://conwaylife.com/forums/viewtopic.php?p=9365#p9365