# A006782 (b-file synthesized from sequence entry)
1 1
2 0
3 1
4 2
5 9
6 36
7 154
8 684
9 3128
10 14666
11 70258
12 342766
13 1698625
14 8532410
15 43368153
16 222729492
17 1154455161
18 6033034032
19 31760434883
20 168311948410
21 897327111964
22 4810159375532
23 25914118276362