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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 2 |
| 4 | -1 |
| 5 | -2 |
| 6 | 6 |
| 7 | 8 |
| 8 | -6 |
| 9 | -8 |
| 10 | 15 |
| 11 | 18 |
| 12 | -15 |
| 13 | -18 |
| 14 | 28 |
| 15 | 32 |
| 16 | -28 |
| 17 | -32 |
| 18 | 45 |
| 19 | 50 |
| 20 | -45 |
| 21 | -50 |
| 22 | 66 |
| 23 | 72 |
| 24 | -66 |
| 25 | -72 |
| 26 | 91 |
| 27 | 98 |
| 28 | -91 |
| 29 | -98 |
| 30 | 120 |
| 31 | 128 |
| 32 | -120 |
| 33 | -128 |
| 34 | 153 |
| 35 | 162 |
| 36 | -153 |
| 37 | -162 |
| 38 | 190 |
| 39 | 200 |
| 40 | -190 |
| 41 | -200 |
| 42 | 231 |
| 43 | 242 |
| 44 | -231 |
| 45 | -242 |
| 46 | 276 |
| 47 | 288 |
| 48 | -276 |
| 49 | -288 |
| 50 | 325 |
| 51 | 338 |
| 52 | -325 |
| 53 | -338 |
| 54 | 378 |
| 55 | 392 |
| 56 | -378 |
| 57 | -392 |
| 58 | 435 |
| 59 | 450 |
| 60 | -435 |
| 61 | -450 |
| 62 | 496 |
| 63 | 512 |
| 64 | -496 |
| 65 | -512 |
| 66 | 561 |
[1,2,-1,-2,6,8,-6,-8,15,18,-15,-18,28,32,-28,-32, 45,50,-45,-50,66,72,-66,-72,91,98,-91,-98,120,128, -120,-128,153,162,-153,-162,190,200,-190,-200,231, 242,-231,-242,276,288,-276,-288,325,338,-325,-338, 378,392,-378,-392,435,450,-435,-450,496,512,-496, -512,561] |