# A005952 (b-file synthesized from sequence entry)
0 1
1 0
2 840
3 2560
4 26376
5 30720
6 204960
7 168960
8 843528
9 593920
10 2625840
11 1605120
12 6435744
13 3717120
14 14118720
15 7633920
16 26992392
17 14192640
18 49806120
19 24752640
20 82451376