# A005978 (b-file synthesized from sequence entry)
1 0
2 0
3 0
4 0
5 1
6 4
7 19
8 93
9 539
10 3474
11 24856
12 192972
13 1613219
14 14410374
15 136920388
16 1378542639
17 14663082556
18 164340455701
19 1936286904952
20 23932267735948
21 309701296575063