| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 1 |
| 3 | 0 |
| 4 | -4 |
| 5 | 0 |
| 6 | 120 |
| 7 | 0 |
| 8 | -12096 |
| 9 | 0 |
| 10 | 3024000 |
| 11 | 0 |
| 12 | -1576143360 |
| 13 | 0 |
| 14 | 1525620096000 |
| 15 | 0 |
| 16 | -2522591034163200 |
| 17 | 0 |
| 18 | 6686974460694528000 |
| 19 | 0 |
| 20 | -27033456071346536448000 |
| 21 | 0 |
| 22 | 160078872315904478576640000 |
| 23 | 0 |
| 24 | -1342964491649083924630732800000 |
| 25 | 0 |
[1,-1,1,0,-4,0,120,0,-12096,0,3024000,0, -1576143360,0,1525620096000,0,-2522591034163200,0, 6686974460694528000,0,-27033456071346536448000,0, 160078872315904478576640000,0, -1342964491649083924630732800000,0] |