# A007161 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 15
4 62
5 262
6 1148
7 5123
8 23316
9 107570
10 502664
11 2372786
12 11302858
13 54256236
14 262226900
15 1274944859
16 6231845040
17 30605344282
18 150948390672
19 747356368322
20 3713140528364
21 18506907541124
22 92509837573736
23 463660345091686