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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 6 |
| 4 | 4 |
| 5 | 0 |
| 6 | -2 |
| 7 | 14 |
| 8 | -100 |
| 9 | 792 |
| 10 | -6996 |
| 11 | 68508 |
| 12 | -737882 |
| 13 | 8676200 |
| 14 | -110627142 |
| 15 | 1520662410 |
| 16 | -22418697948 |
| 17 | 352885526856 |
| 18 | -5907074659016 |
| 19 | 104782694989616 |
| 20 | -1963418893492364 |
| 21 | 38753471698684512 |
| 22 | -803656781974363412 |
| 23 | 17469671114170029708 |
| 24 | -397223288562294817330 |
| 25 | 9429329994809282773300 |
[1,2,4,6,4,0,-2,14,-100,792,-6996,68508,-737882, 8676200,-110627142,1520662410,-22418697948, 352885526856,-5907074659016,104782694989616, -1963418893492364,38753471698684512, -803656781974363412,17469671114170029708, -397223288562294817330,9429329994809282773300] |