# A251574 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 40
4 712
5 18784
6 663424
7 29480896
8 1581976960
9 99585422848
10 7198258087936
11 587699970912256
12 53497834761985024
13 5372784803063664640
14 590164397145095421952
15 70386834555048578596864
16 9058611906733586004803584
17 1251310862246447324484468736
18 184665445630564847038730076160