# A149272 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 11
4 42
5 132
6 512
7 1737
8 6772
9 23922
10 93618
11 339030
12 1330402
13 4898974
14 19264646
15 71788549
16 282770996
17 1063149998
18 4193389956
19 15875202814
20 62687736884
21 238629003248
22 943200410068
23 3606546108418
24 14266939843816
25 54756695145968
26 216764481087652
27 834569354875476
28 3305876625351364