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