# A081685 (b-file synthesized from sequence entry)
0 1
1 0
2 -2
3 24
4 382
5 3480
6 26398
7 183624
8 1217662
9 7844280
10 49595998
11 309603624
12 1915345342
13 11771312280
14 71987479198
15 438579414024
16 2664184199422
17 16146411375480
18 97676153291998
19 590010215086824
20 3559688013155902
21 21455704981601880
22 129219894496730398