# A138897 (b-file synthesized from sequence entry)
2 3
3 20
4 420
5 18144
6 1330560
7 148262400
8 23351328000
9 4940103168000
10 1351612226764800
11 464463110651904000
12 195848611658219520000
13 99430833611096064000000
14 59828953024276660224000000
15 42103628541617628354969600000
16 34261827725741345073856512000000
17 31923961833867229762934538240000000