# A318297 (b-file synthesized from sequence entry)
1 1
2 18
3 2760
4 1153488
5 928609920
6 1224288172800
7 2398694768870400
8 6543329233529088000
9 23715268426751879577600
10 110245593949982051033088000
11 639537254337962130647777280000
12 4528740191242360945670704005120000
13 38446695454134018174768929636352000000