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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 3 |
| 3 | -13 |
| 4 | 19 |
| 5 | -77 |
| 6 | 179 |
| 7 | -461 |
| 8 | 1075 |
| 9 | -3021 |
| 10 | 7219 |
| 11 | -17357 |
| 12 | 44083 |
| 13 | -103373 |
| 14 | 257075 |
| 15 | -627661 |
| 16 | 1469491 |
| 17 | -3511245 |
| 18 | 8547379 |
| 19 | -19764173 |
| 20 | 47344691 |
| 21 | -112038861 |
| 22 | 261254195 |
| 23 | -611161037 |
| 24 | 1435659315 |
| 25 | -3329070029 |
| 26 | 7743892531 |
| 27 | -18025911245 |
| 28 | 41566759987 |
| 29 | -95872193485 |
[1,-1,3,-13,19,-77,179,-461,1075,-3021,7219, -17357,44083,-103373,257075,-627661,1469491, -3511245,8547379,-19764173,47344691,-112038861, 261254195,-611161037,1435659315,-3329070029, 7743892531,-18025911245,41566759987,-95872193485] |