# A066289 (b-file synthesized from sequence entry) 1 1 2 6 3 120 4 672 5 30240 6 32760 7 31998395520 8 796928461056000 9 212517062615531520 10 680489641226538823680000 11 13297004660164711617331200000 12 1534736870451951230417633280000 13 6070066569710805693016339910206758877366156437562171488352958895095808000000000