# A002864 (b-file synthesized from sequence entry)
1 0
2 0
3 1
4 1
5 2
6 3
7 7
8 18
9 41
10 123
11 367
12 1288
13 4878
14 19536
15 85263
16 379799
17 1769979
18 8400285
19 40619385
20 199631989
21 990623857
22 4976016485
23 25182878921
24 128564665125