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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 1 |
| 3 | -2 |
| 4 | 2 |
| 5 | -3 |
| 6 | 4 |
| 7 | -6 |
| 8 | 7 |
| 9 | -9 |
| 10 | 12 |
| 11 | -14 |
| 12 | 18 |
| 13 | -22 |
| 14 | 28 |
| 15 | -34 |
| 16 | 41 |
| 17 | -50 |
| 18 | 60 |
| 19 | -72 |
| 20 | 86 |
| 21 | -105 |
| 22 | 124 |
| 23 | -146 |
| 24 | 174 |
| 25 | -204 |
| 26 | 240 |
| 27 | -282 |
| 28 | 332 |
| 29 | -386 |
| 30 | 450 |
| 31 | -524 |
| 32 | 606 |
| 33 | -703 |
| 34 | 812 |
| 35 | -940 |
| 36 | 1082 |
| 37 | -1243 |
| 38 | 1428 |
| 39 | -1636 |
| 40 | 1873 |
| 41 | -2140 |
| 42 | 2448 |
| 43 | -2788 |
| 44 | 3172 |
| 45 | -3610 |
| 46 | 4096 |
| 47 | -4646 |
| 48 | 5264 |
| 49 | -5962 |
[1,-1,1,-2,2,-3,4,-6,7,-9,12,-14,18,-22,28,-34,41, -50,60,-72,86,-105,124,-146,174,-204,240,-282,332, -386,450,-524,606,-703,812,-940,1082,-1243,1428, -1636,1873,-2140,2448,-2788,3172,-3610,4096,-4646, 5264,-5962] |