# A072847 (b-file synthesized from sequence entry)
1 2
2 3
3 6
4 8
5 21
6 23
7 50
8 105
9 143
10 221
11 634
12 770
13 1197
14 2996
15 5489
16 7129
17 18673
18 25236
19 46246
20 96437
21 179480
22 298091
23 425614