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| n | a(n) |
|---|---|
| 0 | -1 |
| 1 | -2 |
| 2 | -4 |
| 3 | -8 |
| 4 | -8 |
| 5 | -6 |
| 6 | 40 |
| 7 | 132 |
| 8 | 400 |
| 9 | 504 |
| 10 | 76 |
| 11 | -4960 |
| 12 | -18528 |
| 13 | -56998 |
| 14 | -94176 |
| 15 | -58896 |
| 16 | 617216 |
| 17 | 2911128 |
| 18 | 9741760 |
| 19 | 19739472 |
| 20 | 21657312 |
| 21 | -75073186 |
| 22 | -483271024 |
| 23 | -1800924184 |
| 24 | -4274295720 |
| 25 | -6374947674 |
| 26 | 7150661892 |
| 27 | 81254492928 |
| 28 | 345397065128 |
| 29 | 937137978804 |
| 30 | 1717431001440 |
[-1,-2,-4,-8,-8,-6,40,132,400,504,76,-4960,-18528, -56998,-94176,-58896,617216,2911128,9741760, 19739472,21657312,-75073186,-483271024, -1800924184,-4274295720,-6374947674,7150661892, 81254492928,345397065128,937137978804, 1717431001440] |