# A337594 (b-file synthesized from sequence entry) 0 1 1 1 2 6 3 58 4 920 5 21176 6 654960 7 26114768 8 1298070912 9 78359732608 10 5630565514496 11 473796572027648 12 46060380961356800 13 5114737212582603776 14 642502387594286036992 15 90542358999393528670208 16 14209873001490130067095552 17 2467784343879850163370295296 18 471558856613839054976849608704