# A012889 (b-file synthesized from sequence entry)
0 0
1 2
2 -1
3 17
4 -54
5 677
6 -4950
7 65145
8 -752024
9 11468069
10 -176381640
11 3165529275
12 -59818647768
13 1251370749059
14 -27828301203248
15 668331142030125
16 -17039769301121760
17 462939633071828473
18 -13293952511690952000