n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 0 |
4 | 1 |
5 | 20 |
6 | 360 |
7 | 6860 |
8 | 143360 |
9 | 3306744 |
10 | 84000000 |
11 | 2338460520 |
12 | 70946979840 |
13 | 2332989862060 |
14 | 82726831323136 |
15 | 3148511132812500 |
16 | 128071114403348480 |
17 | 5546563698427324720 |
18 | 254873089955815096320 |
19 | 12387799656377835411984 |
[0,0,0,1,20,360,6860,143360,3306744,84000000, 2338460520,70946979840,2332989862060, 82726831323136,3148511132812500, 128071114403348480,5546563698427324720, 254873089955815096320,12387799656377835411984] |