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| n | a(n) |
|---|---|
| 1 | -1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 7 |
| 5 | -1 |
| 6 | 6 |
| 7 | 13 |
| 8 | -1 |
| 9 | 10 |
| 10 | 19 |
| 11 | -1 |
| 12 | 12 |
| 13 | -1 |
| 14 | -1 |
| 15 | 25 |
| 16 | 21 |
| 17 | -1 |
| 18 | 18 |
| 19 | 37 |
| 20 | -1 |
| 21 | 26 |
| 22 | 43 |
| 23 | -1 |
| 24 | 24 |
| 25 | -1 |
| 26 | -1 |
| 27 | 34 |
| 28 | 39 |
| 29 | -1 |
| 30 | 38 |
| 31 | 61 |
| 32 | -1 |
| 33 | -1 |
| 34 | 67 |
| 35 | -1 |
| 36 | 30 |
| 37 | 73 |
| 38 | -1 |
| 39 | -1 |
| 40 | 57 |
| 41 | -1 |
| 42 | 52 |
| 43 | -1 |
| 44 | -1 |
| 45 | 50 |
| 46 | -1 |
| 47 | -1 |
| 48 | 42 |
| 49 | 97 |
| 50 | -1 |
| 51 | 101 |
| 52 | 103 |
| 53 | -1 |
| 54 | 54 |
| 55 | 109 |
| 56 | 91 |
| 57 | 74 |
| 58 | -1 |
| 59 | -1 |
| 60 | 75 |
| 61 | -1 |
| 62 | -1 |
| 63 | 82 |
| 64 | 93 |
| 65 | -1 |
| 66 | 86 |
| 67 | -1 |
| 68 | -1 |
| 69 | 137 |
| 70 | 139 |
| 71 | -1 |
| 72 | 60 |
| 73 | -1 |
| 74 | -1 |
[-1,3,4,7,-1,6,13,-1,10,19,-1,12,-1,-1,25,21,-1, 18,37,-1,26,43,-1,24,-1,-1,34,39,-1,38,61,-1,-1, 67,-1,30,73,-1,-1,57,-1,52,-1,-1,50,-1,-1,42,97, -1,101,103,-1,54,109,91,74,-1,-1,75,-1,-1,82,93, -1,86,-1,-1,137,139,-1,60,-1,-1] |