# A009336 (b-file synthesized from sequence entry)
0 0
1 1
2 -1
3 -2
4 4
5 20
6 -61
7 -296
8 1184
9 9680
10 -49201
11 -393120
12 2361844
13 26927680
14 -191422141
15 -2138039424
16 17147588384
17 250712561920
18 -2289437638081
19 -32881696158208
20 329955144475204
21 5885687604556800
22 -65643617893832221