# A174668 (b-file synthesized from sequence entry)
1 1
2 2
3 24
4 216
5 3120
6 54720
7 1239840
8 32618880
9 981227520
10 33479308800
11 1279972108800
12 53991144345600
13 2490957768499200
14 124892840469196800
15 6761466317878272000
16 393017221207683072000
17 24412776645959589888000
18 1613947446288417816576000
19 113146793902812592226304000