# A131448 (b-file synthesized from sequence entry)
1 1
2 2
3 2
4 24
5 40
6 144
7 5040
8 40320
9 6048
10 6048
11 19958400
12 53222400
13 53222400
14 87178291200
15 118879488000
16 5230697472000
17 8083805184000
18 3201186852864000
19 40548366802944000
20 2432902008176640000
21 17030314057236480000