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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -2 |
| 3 | 0 |
| 4 | 26 |
| 5 | 0 |
| 6 | -1378 |
| 7 | 0 |
| 8 | 141202 |
| 9 | 0 |
| 10 | -22716418 |
| 11 | 0 |
| 12 | 5218302090 |
| 13 | 0 |
| 14 | -1619288968386 |
| 15 | 0 |
| 16 | 653379470919714 |
| 17 | 0 |
| 18 | -333014944014777730 |
| 19 | 0 |
| 20 | 209463165121436380282 |
| 21 | 0 |
| 22 | -159492000935562428176162 |
| 23 | 0 |
| 24 | 144654795258284936534929586 |
| 25 | 0 |
[1,1,-2,0,26,0,-1378,0,141202,0,-22716418,0, 5218302090,0,-1619288968386,0,653379470919714,0, -333014944014777730,0,209463165121436380282,0, -159492000935562428176162,0, 144654795258284936534929586,0] |