# A120915 (b-file synthesized from sequence entry)
0 1
1 4
2 20
3 116
4 720
5 4656
6 30996
7 210896
8 1459536
9 10239796
10 72651184
11 520328112
12 3756512912
13 27307671040
14 199705789248
15 1468209751856
16 10844681408064
17 80437588353600
18 598867568439828
19 4473784063109904
20 33524058847464912