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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | -1 |
| 4 | -4 |
| 5 | -4 |
| 6 | 1 |
| 7 | 7 |
| 8 | 7 |
| 9 | -1 |
| 10 | -10 |
| 11 | -10 |
| 12 | 1 |
| 13 | 13 |
| 14 | 13 |
| 15 | -1 |
| 16 | -16 |
| 17 | -16 |
| 18 | 1 |
| 19 | 19 |
| 20 | 19 |
| 21 | -1 |
| 22 | -22 |
| 23 | -22 |
| 24 | 1 |
| 25 | 25 |
| 26 | 25 |
| 27 | -1 |
| 28 | -28 |
| 29 | -28 |
| 30 | 1 |
| 31 | 31 |
| 32 | 31 |
| 33 | -1 |
| 34 | -34 |
| 35 | -34 |
| 36 | 1 |
| 37 | 37 |
| 38 | 37 |
| 39 | -1 |
| 40 | -40 |
| 41 | -40 |
| 42 | 1 |
| 43 | 43 |
| 44 | 43 |
| 45 | -1 |
| 46 | -46 |
| 47 | -46 |
| 48 | 1 |
| 49 | 49 |
| 50 | 49 |
| 51 | -1 |
| 52 | -52 |
| 53 | -52 |
| 54 | 1 |
| 55 | 55 |
| 56 | 55 |
| 57 | -1 |
| 58 | -58 |
| 59 | -58 |
| 60 | 1 |
| 61 | 61 |
| 62 | 61 |
| 63 | -1 |
[1,1,1,-1,-4,-4,1,7,7,-1,-10,-10,1,13,13,-1,-16, -16,1,19,19,-1,-22,-22,1,25,25,-1,-28,-28,1,31,31, -1,-34,-34,1,37,37,-1,-40,-40,1,43,43,-1,-46,-46, 1,49,49,-1,-52,-52,1,55,55,-1,-58,-58,1,61,61,-1] |