# A001797 (b-file synthesized from sequence entry)
1 2
2 20
3 110
4 2600
5 16150
6 208012
7 1376550
8 74437200
9 511755750
10 7134913500
11 50315410002
12 1433226830360
13 10292051290430
14 148889972762300
15 1083802983548950
16 126935005433253024
17 933787075442258310
18 13799767368300523260