n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 1 |
3 | 2 |
4 | 6 |
5 | 20 |
6 | 240 |
7 | 420 |
8 | 2688 |
9 | 18144 |
10 | 120960 |
11 | 2661120 |
12 | 7983360 |
13 | 103783680 |
14 | 1037836800 |
15 | 12454041600 |
16 | 149448499200 |
17 | 1693749657600 |
18 | 60974987673600 |
19 | 289631191449600 |
20 | 5792623828992000 |
21 | 121645100408832000 |
22 | 3568256278659072000 |
23 | 30776210403434496000 |
24 | 738629049682427904000 |
25 | 12310484161373798400000 |
[1,1,1,2,6,20,240,420,2688,18144,120960,2661120, 7983360,103783680,1037836800,12454041600, 149448499200,1693749657600,60974987673600, 289631191449600,5792623828992000, 121645100408832000,3568256278659072000, 30776210403434496000,738629049682427904000, 12310484161373798400000] |