# A149431 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 13
4 45
5 171
6 689
7 2756
8 11351
9 47976
10 204381
11 878826
12 3824025
13 16776688
14 74021638
15 328681019
16 1467532698
17 6581442360
18 29637099404
19 133969162219
20 607582367783
21 2763746150889
22 12606655549991
23 57648997909311
24 264223264007648
25 1213578131312042
26 5584897636305793
27 25748047536912449