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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | -4 |
| 4 | 56 |
| 5 | -1452 |
| 6 | 58368 |
| 7 | -3339220 |
| 8 | 257978168 |
| 9 | -25928865116 |
| 10 | 3293850854208 |
| 11 | -516648260338724 |
| 12 | 98140914400430840 |
| 13 | -22212891796114092556 |
| 14 | 5908226316995291448256 |
| 15 | -1824964039545848666778100 |
| 16 | 647939176919565713349368184 |
| 17 | -262058639306505158896089030332 |
| 18 | 119788326167873858048176581362560 |
| 19 | -61452317226714509108846922021817924 |
[1,1,-4,56,-1452,58368,-3339220,257978168, -25928865116,3293850854208,-516648260338724, 98140914400430840,-22212891796114092556, 5908226316995291448256,-1824964039545848666778100, 647939176919565713349368184, -262058639306505158896089030332, 119788326167873858048176581362560, -61452317226714509108846922021817924] |