# A002462 (b-file synthesized from sequence entry)
0 1
1 1
2 9
3 50
4 1225
5 7938
6 106722
7 736164
8 41409225
9 295488050
10 4266847442
11 31102144164
12 914057459042
13 6760780022500
14 100583849722500
15 751920156592200
16 90324408810638025
17 680714748752836050
18 10294760089163261250
19 78080479568224402500
20 2375208188465386324050