# A013131 (b-file synthesized from sequence entry)
0 1
1 2
2 4
3 7
4 8
5 17
6 214
7 1761
8 8632
9 38969
10 381754
11 5371821
12 56522540
13 533244077
14 6087452310
15 95701880241
16 1458087413200
17 21713687902033
18 333863833250482
19 6101409790911765
20 114840891055289940
21 2263678163011472213