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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 1 |
| 3 | -1 |
| 4 | 2 |
| 5 | -3 |
| 6 | 4 |
| 7 | -5 |
| 8 | 7 |
| 9 | -10 |
| 10 | 12 |
| 11 | -15 |
| 12 | 20 |
| 13 | -26 |
| 14 | 32 |
| 15 | -39 |
| 16 | 50 |
| 17 | -63 |
| 18 | 76 |
| 19 | -92 |
| 20 | 114 |
| 21 | -140 |
| 22 | 168 |
| 23 | -201 |
| 24 | 244 |
| 25 | -295 |
| 26 | 350 |
| 27 | -415 |
| 28 | 496 |
| 29 | -591 |
| 30 | 696 |
| 31 | -818 |
| 32 | 967 |
| 33 | -1140 |
| 34 | 1332 |
| 35 | -1554 |
| 36 | 1820 |
| 37 | -2126 |
| 38 | 2468 |
| 39 | -2861 |
| 40 | 3324 |
| 41 | -3855 |
| 42 | 4448 |
| 43 | -5126 |
| 44 | 5916 |
| 45 | -6816 |
| 46 | 7824 |
| 47 | -8970 |
| 48 | 10292 |
| 49 | -11793 |
| 50 | 13471 |
| 51 | -15372 |
| 52 | 17548 |
| 53 | -20007 |
[1,-1,1,-1,2,-3,4,-5,7,-10,12,-15,20,-26,32,-39, 50,-63,76,-92,114,-140,168,-201,244,-295,350,-415, 496,-591,696,-818,967,-1140,1332,-1554,1820,-2126, 2468,-2861,3324,-3855,4448,-5126,5916,-6816,7824, -8970,10292,-11793,13471,-15372,17548,-20007] |