# A002221 (b-file synthesized from sequence entry)
1 1
2 5
3 15
4 55
5 140
6 448
7 1022
8 2710
9 6048
10 14114
11 28831
12 64091
13 123649
14 251295
15 476835
16 916972
17 1654044
18 3080159
19 5377431
20 9624588
21 16490017
22 28433473
23 47423409
24 80279375