# A052832 (b-file synthesized from sequence entry)
0 0
1 0
2 2
3 6
4 36
5 240
6 2040
7 20160
8 231840
9 3024000
10 44271360
11 718502400
12 12813292800
13 249080832000
14 5243151513600
15 118824010905600
16 2884729655808000
17 74694359900160000
18 2054806272110592000
19 59849389401145344000
20 1840003788783992832000
21 59545276650123264000000