# A051893 (b-file synthesized from sequence entry)
1 1
2 1
3 5
4 50
5 850
6 22100
7 817700
8 40885000
9 2657525000
10 217917050000
11 22009622050000
12 2685173890100000
13 389350214064500000
14 66189536390965000000
15 13039338669020105000000
16 2946890539198543730000000
17 757350868574025738610000000
18 219631751886467464196900000000