# A366760 (b-file synthesized from sequence entry) 0 1 1 1 2 2 3 6 4 20 5 110 6 612 7 4970 8 39600 9 337680 10 3298900 11 39916800 12 442155168 13 6151996372 14 83387930692 15 1282826630160 16 19089488332800 17 355148307803520 18 5427568925856000 19 119931789135468100 20 2432901890279317572 21 49902667163053013232 22 1073067539495604750240