# A075352 (b-file synthesized from sequence entry)
1 1
2 2
3 12
4 30
5 504
6 1320
7 43680
8 116280
9 6375600
10 17100720
11 1402410240
12 3776965920
13 8835488640
14 1022755734000
15 2478652606080
16 380634949094400
17 945378254620800
18 186127248627129600
19 470489622136934400
20 115590003914312928000