# A068200 (b-file synthesized from sequence entry)
0 1
1 2
2 6
3 24
4 120
5 696
6 4536
7 32568
8 254136
9 2133816
10 19130040
11 182000952
12 1828296888
13 19311334200
14 213709376184
15 2470302259512
16 29746381049016
17 372270346391352
18 4831940144914104
19 64925998174811448
20 901626111996723384
21 12920858504042924856