n | a(n) |
---|---|
0 | 1 |
1 | 0 |
2 | 0 |
3 | 0 |
4 | 6 |
5 | 24 |
6 | 120 |
7 | 720 |
8 | 6300 |
9 | 58464 |
10 | 586656 |
11 | 6384960 |
12 | 76471560 |
13 | 994831200 |
14 | 13939507296 |
15 | 209097854784 |
16 | 3345235180560 |
17 | 56866395720960 |
18 | 1023601917024000 |
19 | 19448577603454464 |
20 | 388972171805410656 |
21 | 8168409582839579520 |
22 | 179704944537482689920 |
[1,0,0,0,6,24,120,720,6300,58464,586656,6384960, 76471560,994831200,13939507296,209097854784, 3345235180560,56866395720960,1023601917024000, 19448577603454464,388972171805410656, 8168409582839579520,179704944537482689920] |