n | a(n) |
---|---|
2 | 1 |
3 | 2 |
4 | 6 |
5 | 18 |
6 | 60 |
7 | 204 |
8 | 720 |
9 | 2580 |
10 | 9408 |
11 | 34668 |
12 | 129024 |
13 | 483672 |
14 | 1824768 |
15 | 6919752 |
16 | 26357976 |
17 | 100778472 |
18 | 386591304 |
19 | 1487221056 |
20 | 5735785176 |
21 | 22170562656 |
22 | 85866332760 |
23 | 333151068528 |
24 | 1294658562912 |
25 | 5038469947992 |
26 | 19634243736168 |
[1,2,6,18,60,204,720,2580,9408,34668,129024, 483672,1824768,6919752,26357976,100778472, 386591304,1487221056,5735785176,22170562656, 85866332760,333151068528,1294658562912, 5038469947992,19634243736168] |