n | a(n) |
---|---|
1 | 0 |
2 | 1 |
3 | 6 |
4 | 45 |
5 | 420 |
6 | 4800 |
7 | 65520 |
8 | 1045170 |
9 | 19126800 |
10 | 395448480 |
11 | 9120988800 |
12 | 232248416400 |
13 | 6471820555200 |
14 | 195912193276800 |
15 | 6402199349145600 |
16 | 224636583525354000 |
17 | 8423131243022496000 |
18 | 336138596955120960000 |
19 | 14224375944427993344000 |
20 | 636224790017466730080000 |
[0,1,6,45,420,4800,65520,1045170,19126800, 395448480,9120988800,232248416400,6471820555200, 195912193276800,6402199349145600, 224636583525354000,8423131243022496000, 336138596955120960000,14224375944427993344000, 636224790017466730080000] |