# A009676 (b-file synthesized from sequence entry)
0 0
1 1
2 -1
3 5
4 -24
5 166
6 -1350
7 13082
8 -145376
9 1827376
10 -25592400
11 395118272
12 -6664254432
13 121895495632
14 -2402856317680
15 50776649007632
16 -1144984530078720
17 27440409496420096
18 -696465326225541888