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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | -4 |
| 4 | 38 |
| 5 | -646 |
| 6 | 17124 |
| 7 | -651120 |
| 8 | 33563760 |
| 9 | -2251415376 |
| 10 | 190506294720 |
| 11 | -19843054116480 |
| 12 | 2494435702953600 |
| 13 | -372324067662349440 |
| 14 | 65089674982557308160 |
| 15 | -13172994619821785548800 |
| 16 | 3055455516855073351219200 |
| 17 | -805168341051328705189939200 |
[0,1,1,-4,38,-646,17124,-651120,33563760, -2251415376,190506294720,-19843054116480, 2494435702953600,-372324067662349440, 65089674982557308160,-13172994619821785548800, 3055455516855073351219200, -805168341051328705189939200] |