# A009169 (b-file synthesized from sequence entry)
0 1
1 0
2 1
3 -3
4 4
5 20
6 -224
7 1344
8 -5144
9 -4320
10 356896
11 -4755520
12 42368536
13 -207434448
14 -1593929336
15 61487349000
16 -997231605824
17 9976381236224
18 -16539522000704
19 -1929601048449600
20 51992648244966016
21 -800205465246136320