n | a(n) |
---|---|
1 | 4 |
2 | 12 |
3 | 56 |
4 | 216 |
5 | 1240 |
6 | 5040 |
7 | 31992 |
8 | 139968 |
9 | 828576 |
10 | 3720000 |
11 | 25238048 |
12 | 104509440 |
13 | 803499840 |
14 | 3687014016 |
15 | 24373440000 |
16 | 110630707200 |
17 | 790546192128 |
18 | 3463116249600 |
19 | 25522921047520 |
20 | 108957312000000 |
21 | 816244048599840 |
22 | 3924124012353600 |
23 | 26682733370563200 |
[4,12,56,216,1240,5040,31992,139968,828576, 3720000,25238048,104509440,803499840,3687014016, 24373440000,110630707200,790546192128, 3463116249600,25522921047520,108957312000000, 816244048599840,3924124012353600, 26682733370563200] |