# A126403 (b-file synthesized from sequence entry)
0 1
1 16
2 74
3 350
4 1668
5 7986
6 38348
7 184524
8 889230
9 4290030
10 20714382
11 100083072
12 483793208
13 2339478320
14 11316186924
15 54748710158
16 264922095330
17 1282082867386
18 6205185792886
19 30034782040334
20 145384379570694