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| n | a(n) |
|---|---|
| 2 | -1 |
| 3 | 1 |
| 4 | -4 |
| 5 | -16 |
| 6 | -27 |
| 7 | 441 |
| 8 | -1024 |
| 9 | -1024 |
| 10 | 34445 |
| 11 | -13778944 |
| 12 | 82719025 |
| 13 | 48841786125 |
| 14 | -67649929216 |
| 15 | -564926611456 |
| 16 | -153908556861703 |
| 17 | -25481517249593344 |
| 18 | 2456184022341328125 |
| 19 | -399780402627654713344 |
| 20 | -14448269983744 |
| 21 | -214168150727821285287075 |
[-1,1,-4,-16,-27,441,-1024,-1024,34445,-13778944, 82719025,48841786125,-67649929216,-564926611456, -153908556861703,-25481517249593344, 2456184022341328125,-399780402627654713344, -14448269983744,-214168150727821285287075] |