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