# A006820 (b-file synthesized from sequence entry)
0 1
1 0
2 0
3 0
4 0
5 1
6 1
7 2
8 6
9 16
10 59
11 265
12 1544
13 10778
14 88168
15 805491
16 8037418
17 86221634
18 985870522
19 11946487647
20 152808063181
21 2056692014474
22 29051272833609
23 429668180677439
24 6640165204855036
25 107026584471569605
26 1796101588825595008
27 31333997930603283531
28 567437240683788292989