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