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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -9 |
| 3 | 99 |
| 4 | -1344 |
| 5 | 21875 |
| 6 | -416016 |
| 7 | 9058973 |
| 8 | -222298112 |
| 9 | 6069587661 |
| 10 | -182500000000 |
| 11 | 5991545082831 |
| 12 | -213243402387456 |
| 13 | 8177627877990831 |
| 14 | -336138206473129984 |
| 15 | 14742427642822265625 |
| 16 | -687141216745680797696 |
| 17 | 33916850737339807331257 |
[1,-9,99,-1344,21875,-416016,9058973,-222298112, 6069587661,-182500000000,5991545082831, -213243402387456,8177627877990831, -336138206473129984,14742427642822265625, -687141216745680797696,33916850737339807331257] |