n | a(n) |
---|---|
0 | 1 |
1 | 3 |
2 | 18 |
3 | 162 |
4 | 1944 |
5 | 29160 |
6 | 524880 |
7 | 11022480 |
8 | 264539520 |
9 | 7142567040 |
10 | 214277011200 |
11 | 7071141369600 |
12 | 254561089305600 |
13 | 9927882482918400 |
14 | 416971064282572800 |
15 | 18763697892715776000 |
16 | 900657498850357248000 |
17 | 45933532441368219648000 |
18 | 2480410751833883860992000 |
[1,3,18,162,1944,29160,524880,11022480,264539520, 7142567040,214277011200,7071141369600, 254561089305600,9927882482918400, 416971064282572800,18763697892715776000, 900657498850357248000,45933532441368219648000, 2480410751833883860992000] |