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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 1 |
| 4 | 4 |
| 5 | -1 |
| 6 | 3 |
| 7 | 6 |
| 8 | -1 |
| 9 | 2 |
| 10 | -1 |
| 11 | -1 |
| 12 | 5 |
| 13 | -1 |
| 14 | -1 |
| 15 | -1 |
| 16 | 4 |
| 17 | -1 |
| 18 | 4 |
| 19 | -1 |
| 20 | -1 |
| 21 | 7 |
| 22 | -1 |
| 23 | -1 |
| 24 | -1 |
| 25 | -1 |
| 26 | -1 |
| 27 | 3 |
| 28 | 6 |
| 29 | -1 |
| 30 | -1 |
| 31 | -1 |
| 32 | -1 |
| 33 | -1 |
| 34 | -1 |
| 35 | -1 |
| 36 | 6 |
| 37 | -1 |
| 38 | -1 |
| 39 | -1 |
| 40 | -1 |
| 41 | -1 |
| 42 | -1 |
| 43 | -1 |
| 44 | -1 |
| 45 | -1 |
| 46 | -1 |
| 47 | 5 |
| 48 | 5 |
| 49 | 8 |
| 50 | -1 |
| 51 | -1 |
| 52 | -1 |
| 53 | -1 |
| 54 | 5 |
| 55 | -1 |
| 56 | -1 |
| 57 | -1 |
| 58 | -1 |
| 59 | -1 |
| 60 | -1 |
| 61 | -1 |
| 62 | -1 |
| 63 | 8 |
| 64 | -1 |
| 65 | -1 |
| 66 | -1 |
| 67 | -1 |
| 68 | -1 |
| 69 | -1 |
| 70 | -1 |
[0,2,1,4,-1,3,6,-1,2,-1,-1,5,-1,-1,-1,4,-1,4,-1, -1,7,-1,-1,-1,-1,-1,3,6,-1,-1,-1,-1,-1,-1,-1,6,-1, -1,-1,-1,-1,-1,-1,-1,-1,-1,5,5,8,-1,-1,-1,-1,5,-1, -1,-1,-1,-1,-1,-1,-1,8,-1,-1,-1,-1,-1,-1,-1] |