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| n | a(n) |
|---|---|
| 1 | -2 |
| 2 | 0 |
| 3 | 1 |
| 4 | -3 |
| 5 | 6 |
| 6 | -9 |
| 7 | 9 |
| 8 | 1 |
| 9 | -36 |
| 10 | 126 |
| 11 | -326 |
| 12 | 726 |
| 13 | -1452 |
| 14 | 2640 |
| 15 | -4356 |
| 16 | 6436 |
| 17 | -8256 |
| 18 | 8568 |
| 19 | -5864 |
| 20 | 456 |
| 21 | -911 |
| 22 | 40106 |
| 23 | -210419 |
| 24 | 733448 |
| 25 | -2085526 |
| 26 | 5200300 |
| 27 | -11748374 |
| 28 | 24416952 |
| 29 | -46909838 |
| 30 | 82930836 |
| 31 | -132479946 |
| 32 | 182029056 |
| 33 | -182029056 |
| 34 | 0 |
| 35 | 670853984 |
| 36 | -2480588544 |
[-2,0,1,-3,6,-9,9,1,-36,126,-326,726,-1452,2640, -4356,6436,-8256,8568,-5864,456,-911,40106, -210419,733448,-2085526,5200300,-11748374, 24416952,-46909838,82930836,-132479946,182029056, -182029056,0,670853984,-2480588544] |