# A251598 (b-file synthesized from sequence entry)
0 1
1 1
2 3
3 15
4 105
5 944
6 10340
7 133055
8 1958060
9 32279090
10 586453658
11 11589971918
12 246518371679
13 5594169454700
14 134456679614850
15 3402014360391645
16 90146180439817440
17 2490533922180210720
18 71468389947184389600
19 2123114263550335500000