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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | -2 |
| 4 | -6 |
| 5 | -6 |
| 6 | 0 |
| 7 | 7 |
| 8 | 7 |
| 9 | -2 |
| 10 | -12 |
| 11 | -12 |
| 12 | 0 |
| 13 | 13 |
| 14 | 13 |
| 15 | -2 |
| 16 | -18 |
| 17 | -18 |
| 18 | 0 |
| 19 | 19 |
| 20 | 19 |
| 21 | -2 |
| 22 | -24 |
| 23 | -24 |
| 24 | 0 |
| 25 | 25 |
| 26 | 25 |
| 27 | -2 |
| 28 | -30 |
| 29 | -30 |
| 30 | 0 |
| 31 | 31 |
| 32 | 31 |
| 33 | -2 |
| 34 | -36 |
| 35 | -36 |
| 36 | 0 |
| 37 | 37 |
| 38 | 37 |
| 39 | -2 |
| 40 | -42 |
| 41 | -42 |
| 42 | 0 |
| 43 | 43 |
| 44 | 43 |
| 45 | -2 |
| 46 | -48 |
| 47 | -48 |
| 48 | 0 |
| 49 | 49 |
| 50 | 49 |
| 51 | -2 |
| 52 | -54 |
| 53 | -54 |
| 54 | 0 |
| 55 | 55 |
| 56 | 55 |
| 57 | -2 |
| 58 | -60 |
| 59 | -60 |
| 60 | 0 |
| 61 | 61 |
| 62 | 61 |
| 63 | -2 |
| 64 | -66 |
| 65 | -66 |
| 66 | 0 |
| 67 | 67 |
| 68 | 67 |
| 69 | -2 |
| 70 | -72 |
| 71 | -72 |
| 72 | 0 |
| 73 | 73 |
| 74 | 73 |
| 75 | -2 |
| 76 | -78 |
| 77 | -78 |
| 78 | 0 |
| 79 | 79 |
| 80 | 79 |
| 81 | -2 |
| 82 | -84 |
[0,1,1,-2,-6,-6,0,7,7,-2,-12,-12,0,13,13,-2,-18, -18,0,19,19,-2,-24,-24,0,25,25,-2,-30,-30,0,31,31, -2,-36,-36,0,37,37,-2,-42,-42,0,43,43,-2,-48,-48, 0,49,49,-2,-54,-54,0,55,55,-2,-60,-60,0,61,61,-2, -66,-66,0,67,67,-2,-72,-72,0,73,73,-2,-78,-78,0, 79,79,-2,-84] |