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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | 25 |
| 5 | -674 |
| 6 | 15211 |
| 7 | -331827 |
| 8 | 5987745 |
| 9 | 15901597 |
| 10 | -13125035449 |
| 11 | 1292056076070 |
| 12 | -103145930581319 |
| 13 | 7462324963409941 |
| 14 | -464957409070517453 |
| 15 | 16313974895147212801 |
| 16 | 2059903411953959582849 |
| 17 | -708700955022151333496910 |
| 18 | 143215213612865558214820303 |
| 19 | -24681846509158429152517973103 |
[1,1,-1,1,25,-674,15211,-331827,5987745,15901597, -13125035449,1292056076070,-103145930581319, 7462324963409941,-464957409070517453, 16313974895147212801,2059903411953959582849, -708700955022151333496910, 143215213612865558214820303, -24681846509158429152517973103] |