# A163087 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 6
4 12
5 30
6 240
7 140
8 840
9 3780
10 15120
11 2772
12 221760
13 12012
14 960960
15 9266400
16 10810800
17 218790
18 7351344000
19 923780
20 16761064320
21 3259095840
22 3910915008
23 16224936
24 41977154419200
25 2028117000
26 249864014400