# A137538 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 6
4 23
5 104
6 532
7 3004
8 18426
9 121393
10 851810
11 6325151
12 49448313
13 405298482
14 3470885747
15 30965656442
16 287083987270
17 2759838731485
18 27458514900626
19 282264050120512
20 2993392570828096
21 32704759586810036
22 367673428857985261