n | a(n) |
---|---|
1 | 1 |
2 | 0 |
3 | 4 |
4 | 4 |
5 | 36 |
6 | 88 |
7 | 432 |
8 | 1408 |
9 | 5776 |
10 | 20736 |
11 | 80320 |
12 | 297792 |
13 | 1132096 |
14 | 4242304 |
15 | 16028928 |
16 | 60276736 |
17 | 227287296 |
18 | 855703552 |
19 | 3224482816 |
20 | 12144337920 |
21 | 45752574976 |
22 | 172339107840 |
23 | 649223532544 |
24 | 2445572276224 |
25 | 9212566081536 |
26 | 34703459811328 |
[1,0,4,4,36,88,432,1408,5776,20736,80320,297792, 1132096,4242304,16028928,60276736,227287296, 855703552,3224482816,12144337920,45752574976, 172339107840,649223532544,2445572276224, 9212566081536,34703459811328] |