n | a(n) |
---|---|
1 | 0 |
2 | 1 |
3 | 2 |
4 | 18 |
5 | 72 |
6 | 720 |
7 | 4320 |
8 | 50400 |
9 | 403200 |
10 | 5443200 |
11 | 54432000 |
12 | 838252800 |
13 | 10059033600 |
14 | 174356582400 |
15 | 2440992153600 |
16 | 47076277248000 |
17 | 753220435968000 |
18 | 16005934264320000 |
19 | 288106816757760000 |
20 | 6690480522485760000 |
21 | 133809610449715200000 |
22 | 3372002183332823040000 |
[0,1,2,18,72,720,4320,50400,403200,5443200, 54432000,838252800,10059033600,174356582400, 2440992153600,47076277248000,753220435968000, 16005934264320000,288106816757760000, 6690480522485760000,133809610449715200000, 3372002183332823040000] |