# A002710 (b-file synthesized from sequence entry)
0 1
1 2
2 6
3 26
4 147
5 892
6 5876
7 40490
8 290020
9 2136488
10 16113254
11 123878966
12 968017330
13 7670113856
14 61510346760
15 498496979754
16 4077605379276
17 33629943832280
18 279413323740280
19 2336935584712872
20 19663001667901339