# A372987 (b-file synthesized from sequence entry)
0 1
1 2
2 6
3 20
4 84
5 360
6 1848
7 9360
8 55440
9 318240
10 2106720
11 13366080
12 96909120
13 668304000
14 5233092480
15 38761632000
16 324451733760
17 2558267712000
18 22711621363200
19 189311810688000
20 1771506466329600
21 15523568476416000
22 152349556104345600
23 1397121162877440000