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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -3 |
| 2 | 6 |
| 3 | -12 |
| 4 | 24 |
| 5 | -45 |
| 6 | 78 |
| 7 | -132 |
| 8 | 222 |
| 9 | -363 |
| 10 | 576 |
| 11 | -900 |
| 12 | 1392 |
| 13 | -2121 |
| 14 | 3180 |
| 15 | -4716 |
| 16 | 6936 |
| 17 | -10098 |
| 18 | 14550 |
| 19 | -20796 |
| 20 | 29520 |
| 21 | -41595 |
| 22 | 58176 |
| 23 | -80856 |
| 24 | 111750 |
| 25 | -153561 |
| 26 | 209820 |
| 27 | -285240 |
| 28 | 385968 |
| 29 | -519840 |
| 30 | 696960 |
| 31 | -930516 |
| 32 | 1237470 |
| 33 | -1639314 |
| 34 | 2163456 |
| 35 | -2845080 |
| 36 | 3728904 |
| 37 | -4871211 |
[1,-3,6,-12,24,-45,78,-132,222,-363,576,-900,1392, -2121,3180,-4716,6936,-10098,14550,-20796,29520, -41595,58176,-80856,111750,-153561,209820,-285240, 385968,-519840,696960,-930516,1237470,-1639314, 2163456,-2845080,3728904,-4871211] |