n | a(n) |
---|---|
1 | 2 |
2 | 6 |
3 | 8 |
4 | 90 |
5 | 288 |
6 | 840 |
7 | 17280 |
8 | 28350 |
9 | 89600 |
10 | 598752 |
11 | 87091200 |
12 | 63063000 |
13 | 402361344000 |
14 | 5003856000 |
15 | 2066448384 |
16 | 976924698750 |
17 | 3766102179840000 |
18 | 15209113920000 |
19 | 5377993912811520000 |
20 | 1646485441080480 |
21 | 89903156428800000 |
[2,6,8,90,288,840,17280,28350,89600,598752, 87091200,63063000,402361344000,5003856000, 2066448384,976924698750,3766102179840000, 15209113920000,5377993912811520000, 1646485441080480,89903156428800000] |