# A091755 (b-file synthesized from sequence entry)
4 1
5 140
6 27720
7 7847840
8 3049446400
9 1564366003200
10 1026108219136000
11 838477001922560000
12 835580445006827520000
13 997744946185930342400000
14 1406513375677181496524800000
15 2311431202054422682730496000000