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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | -2 |
| 3 | -12 |
| 4 | -90 |
| 5 | -968 |
| 6 | -12764 |
| 7 | -200464 |
| 8 | -3674378 |
| 9 | -76958942 |
| 10 | -1814783184 |
| 11 | -47618072204 |
| 12 | -1376556963244 |
| 13 | -43481881639608 |
| 14 | -1490306874257184 |
| 15 | -55091497907730000 |
| 16 | -2185104061817592618 |
| 17 | -92567886910879671396 |
| 18 | -4171638481112174023226 |
[1,-2,-2,-12,-90,-968,-12764,-200464,-3674378, -76958942,-1814783184,-47618072204,-1376556963244, -43481881639608,-1490306874257184, -55091497907730000,-2185104061817592618, -92567886910879671396,-4171638481112174023226] |