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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | -1 |
| 4 | 1 |
| 5 | -1 |
| 6 | 1 |
| 7 | -1 |
| 8 | 2 |
| 9 | -2 |
| 10 | 2 |
| 11 | -3 |
| 12 | 4 |
| 13 | -4 |
| 14 | 4 |
| 15 | -6 |
| 16 | 7 |
| 17 | -7 |
| 18 | 8 |
| 19 | -10 |
| 20 | 12 |
| 21 | -13 |
| 22 | 14 |
| 23 | -17 |
| 24 | 21 |
| 25 | -22 |
| 26 | 24 |
| 27 | -29 |
| 28 | 33 |
| 29 | -36 |
| 30 | 40 |
| 31 | -46 |
| 32 | 53 |
| 33 | -58 |
| 34 | 63 |
| 35 | -73 |
| 36 | 83 |
| 37 | -90 |
| 38 | 99 |
| 39 | -113 |
| 40 | 127 |
| 41 | -138 |
| 42 | 152 |
| 43 | -171 |
| 44 | 191 |
| 45 | -209 |
| 46 | 228 |
| 47 | -255 |
| 48 | 285 |
| 49 | -309 |
| 50 | 338 |
| 51 | -377 |
| 52 | 416 |
| 53 | -453 |
| 54 | 495 |
| 55 | -547 |
| 56 | 603 |
| 57 | -656 |
[1,0,0,-1,1,-1,1,-1,2,-2,2,-3,4,-4,4,-6,7,-7,8, -10,12,-13,14,-17,21,-22,24,-29,33,-36,40,-46,53, -58,63,-73,83,-90,99,-113,127,-138,152,-171,191, -209,228,-255,285,-309,338,-377,416,-453,495,-547, 603,-656] |