n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 6 |
3 | 30 |
4 | 144 |
5 | 680 |
6 | 3168 |
7 | 14560 |
8 | 66048 |
9 | 296064 |
10 | 1313280 |
11 | 5772800 |
12 | 25178112 |
13 | 109078528 |
14 | 469819392 |
15 | 2013388800 |
16 | 8590196736 |
17 | 36507779072 |
18 | 154620002304 |
19 | 652837519360 |
20 | 2748784312320 |
21 | 11544883101696 |
22 | 48378534690816 |
[0,1,6,30,144,680,3168,14560,66048,296064,1313280, 5772800,25178112,109078528,469819392,2013388800, 8590196736,36507779072,154620002304,652837519360, 2748784312320,11544883101696,48378534690816] |