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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -12 |
| 2 | 66 |
| 3 | -232 |
| 4 | 639 |
| 5 | -1596 |
| 6 | 3774 |
| 7 | -8328 |
| 8 | 17283 |
| 9 | -34520 |
| 10 | 66882 |
| 11 | -125568 |
| 12 | 229244 |
| 13 | -409236 |
| 14 | 716412 |
| 15 | -1231048 |
| 16 | 2079237 |
| 17 | -3459264 |
| 18 | 5677832 |
| 19 | -9200232 |
| 20 | 14729592 |
| 21 | -23325752 |
| 22 | 36567222 |
| 23 | -56778888 |
| 24 | 87369483 |
| 25 | -133315692 |
[1,-12,66,-232,639,-1596,3774,-8328,17283,-34520, 66882,-125568,229244,-409236,716412,-1231048, 2079237,-3459264,5677832,-9200232,14729592, -23325752,36567222,-56778888,87369483,-133315692] |