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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 1 |
| 3 | -1 |
| 4 | 1 |
| 5 | -1 |
| 6 | 1 |
| 7 | -2 |
| 8 | 3 |
| 9 | -4 |
| 10 | 5 |
| 11 | -6 |
| 12 | 7 |
| 13 | -8 |
| 14 | 10 |
| 15 | -13 |
| 16 | 17 |
| 17 | -22 |
| 18 | 27 |
| 19 | -33 |
| 20 | 40 |
| 21 | -49 |
| 22 | 61 |
| 23 | -77 |
| 24 | 98 |
| 25 | -123 |
| 26 | 153 |
| 27 | -189 |
| 28 | 233 |
| 29 | -288 |
| 30 | 358 |
| 31 | -448 |
| 32 | 561 |
| 33 | -701 |
| 34 | 872 |
| 35 | -1082 |
| 36 | 1342 |
| 37 | -1666 |
| 38 | 2073 |
| 39 | -2584 |
| 40 | 3223 |
| 41 | -4016 |
| 42 | 4997 |
| 43 | -6212 |
| 44 | 7720 |
| 45 | -9598 |
| 46 | 11942 |
| 47 | -14869 |
| 48 | 18517 |
| 49 | -23053 |
| 50 | 28687 |
[1,-1,1,-1,1,-1,1,-2,3,-4,5,-6,7,-8,10,-13,17,-22, 27,-33,40,-49,61,-77,98,-123,153,-189,233,-288, 358,-448,561,-701,872,-1082,1342,-1666,2073,-2584, 3223,-4016,4997,-6212,7720,-9598,11942,-14869, 18517,-23053,28687] |