# A007683 (b-file synthesized from sequence entry)
1 1
2 -3
3 3
4 9
5 21
6 -33
7 -1173
8 -13515
9 -113739
10 -532209
11 6284379
12 264830061
13 5897799141
14 104393462439
15 1459983940203
16 10308316834293
17 -308010522508395
18 -19576840707893409
19 -726806556195360069
20 -22261372611370303875
21 -591210850189999983099