# A364324 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 24
4 168
5 1560
6 17280
7 221760
8 3265920
9 54069120
10 994291200
11 20118067200
12 444034483200
13 10617070464000
14 273391121203200
15 7542665754624000
16 221969877921792000
17 6940528784437248000
18 229781192298577920000
19 8030036368187817984000
20 295390797322766745600000