# A089057 (b-file synthesized from sequence entry)
3 3
4 12
5 60
6 360
7 2520
8 13440
9 120960
10 1209600
11 13305600
12 159667200
13 2075673600
14 29059430400
15 435891456000
16 6974263296000
17 118562476032000
18 2134124568576000
19 40548366802944000
20 810967336058880000