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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 7 |
| 3 | -65 |
| 4 | 695 |
| 5 | -8081 |
| 6 | 33101 |
| 7 | -422987 |
| 8 | 5564765 |
| 9 | -224617265 |
| 10 | 3076621127 |
| 11 | -42757939841 |
| 12 | 601443961207 |
| 13 | -8546453367505 |
| 14 | 122502619954855 |
| 15 | -65523500154995 |
| 16 | 2857425741902815 |
| 17 | -41776517795212585 |
| 18 | 1841741396312128685 |
| 19 | -27188436143675219435 |
[1,-1,7,-65,695,-8081,33101,-422987,5564765, -224617265,3076621127,-42757939841,601443961207, -8546453367505,122502619954855,-65523500154995, 2857425741902815,-41776517795212585, 1841741396312128685,-27188436143675219435] |