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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -9 |
| 2 | 99 |
| 3 | -1287 |
| 4 | 19089 |
| 5 | -316305 |
| 6 | 5772195 |
| 7 | -114729615 |
| 8 | 2462398785 |
| 9 | -56674425465 |
| 10 | 1390839617475 |
| 11 | -36219350942775 |
| 12 | 996780497137425 |
| 13 | -28887911103276225 |
| 14 | 878916406742849475 |
| 15 | -27996927397669605375 |
[1,-9,99,-1287,19089,-316305,5772195,-114729615, 2462398785,-56674425465,1390839617475, -36219350942775,996780497137425, -28887911103276225,878916406742849475, -27996927397669605375] |