# A058251 (b-file synthesized from sequence entry) 0 1 1 2 2 6 3 120 4 1680 5 36960 6 5765760 7 1568286720 8 536354058240 9 24672286679040 10 2861985254768640 11 2661646286934835200 12 3545312854197200486400 13 5814313080883408797696000 14 10500649424075436288638976000