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