# A361570 (b-file synthesized from sequence entry)
0 1
1 0
2 2
3 12
4 36
5 240
6 2280
7 15120
8 122640
9 1330560
10 13335840
11 136382400
12 1657212480
13 20860519680
14 262278656640
15 3585207225600
16 52249374777600
17 772773281280000
18 11907924610982400
19 193962388523904000
20 3253343368231756800
21 56051640629816832000