# A047139 (b-file synthesized from sequence entry)
0 1
1 2
2 9
3 48
4 261
5 1534
6 9319
7 56808
8 353362
9 2227380
10 14099553
11 89931668
12 577292621
13 3718701300
14 24047442913
15 156059054586
16 1015345651345
17 6621929417524
18 43283675452318
19 283439130488986
20 1859169844171611