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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 5 |
| 5 | -1 |
| 6 | 7 |
| 7 | 8 |
| 8 | 9 |
| 9 | -1 |
| 10 | 11 |
| 11 | -1 |
| 12 | 13 |
| 13 | -1 |
| 14 | 24 |
| 15 | 16 |
| 16 | 17 |
| 17 | -1 |
| 18 | 19 |
| 19 | -1 |
| 20 | 33 |
| 21 | -1 |
| 22 | 23 |
| 23 | -1 |
| 24 | 25 |
| 25 | -1 |
| 26 | 27 |
| 27 | -1 |
| 28 | 29 |
| 29 | -1 |
| 30 | 31 |
| 31 | 32 |
| 32 | 45 |
| 33 | -1 |
| 34 | -1 |
| 35 | -1 |
| 36 | 37 |
| 37 | -1 |
| 38 | -1 |
| 39 | -1 |
| 40 | 41 |
| 41 | -1 |
| 42 | 43 |
| 43 | -1 |
| 44 | 69 |
| 45 | -1 |
| 46 | 47 |
| 47 | -1 |
| 48 | 49 |
| 49 | -1 |
| 50 | -1 |
| 51 | -1 |
| 52 | 53 |
| 53 | -1 |
| 54 | 76 |
| 55 | -1 |
| 56 | 72 |
| 57 | -1 |
| 58 | 59 |
| 59 | -1 |
| 60 | 61 |
| 61 | -1 |
| 62 | 96 |
| 63 | 64 |
| 64 | 85 |
| 65 | -1 |
| 66 | 67 |
| 67 | -1 |
| 68 | -1 |
| 69 | -1 |
| 70 | 71 |
| 71 | -1 |
| 72 | 73 |
| 73 | -1 |
| 74 | -1 |
| 75 | -1 |
| 76 | -1 |
| 77 | -1 |
| 78 | 79 |
| 79 | -1 |
| 80 | 81 |
| 81 | -1 |
| 82 | 83 |
| 83 | -1 |
| 84 | 104 |
| 85 | -1 |
| 86 | -1 |
| 87 | -1 |
[1,3,4,5,-1,7,8,9,-1,11,-1,13,-1,24,16,17,-1,19, -1,33,-1,23,-1,25,-1,27,-1,29,-1,31,32,45,-1,-1, -1,37,-1,-1,-1,41,-1,43,-1,69,-1,47,-1,49,-1,-1, -1,53,-1,76,-1,72,-1,59,-1,61,-1,96,64,85,-1,67, -1,-1,-1,71,-1,73,-1,-1,-1,-1,-1,79,-1,81,-1,83, -1,104,-1,-1,-1] |