n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 0 |
4 | 0 |
5 | 120 |
6 | 1800 |
7 | 16800 |
8 | 126000 |
9 | 834120 |
10 | 5102880 |
11 | 29607600 |
12 | 165526200 |
13 | 901020120 |
14 | 4808987400 |
15 | 25292030280 |
16 | 131542740000 |
17 | 678330198120 |
18 | 3474970629480 |
19 | 17710714165200 |
20 | 89904725757000 |
[0,0,0,0,120,1800,16800,126000,834120,5102880, 29607600,165526200,901020120,4808987400, 25292030280,131542740000,678330198120, 3474970629480,17710714165200,89904725757000] |