# A127116 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 6
4 26
5 143
6 880
7 6820
8 61270
9 612700
10 6740700
11 83088500
12 1211283600
13 17058212600
14 270017301300
15 4560302022000
16 82065335385000
17 1648341372414000
18 34076827548280000
19 725735500635080000
20 17178403115182870000