# A002980 (b-file synthesized from sequence entry)
0 1
1 1
2 0
3 -1
4 24
5 121
6 -480
7 -4201
8 48384
9 478801
10 -4968960
11 -62871601
12 885586944
13 12996863881
14 -203910819840
15 -3476839930201
16 63397697224704
17 1221998040867361
18 -24917358603141120
19 -537278342731116001