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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 2 |
| 7 | -1 |
| 8 | 2 |
| 9 | 2 |
| 10 | 3 |
| 11 | 3 |
| 12 | 2 |
| 13 | 3 |
| 14 | 3 |
| 15 | -1 |
| 16 | 4 |
| 17 | 3 |
| 18 | 3 |
| 19 | 3 |
| 20 | 4 |
| 21 | 4 |
| 22 | 3 |
| 23 | -1 |
| 24 | 4 |
| 25 | 4 |
| 26 | 4 |
| 27 | 3 |
| 28 | -1 |
| 29 | 4 |
| 30 | 5 |
| 31 | -1 |
| 32 | 4 |
| 33 | 4 |
| 34 | 4 |
| 35 | 5 |
| 36 | 4 |
| 37 | 6 |
| 38 | 5 |
| 39 | -1 |
| 40 | 6 |
| 41 | 4 |
| 42 | 5 |
| 43 | 5 |
| 44 | 6 |
| 45 | 5 |
| 46 | 6 |
| 47 | -1 |
| 48 | 4 |
| 49 | 6 |
| 50 | 5 |
| 51 | 5 |
| 52 | 6 |
| 53 | 6 |
| 54 | 5 |
| 55 | -1 |
| 56 | 6 |
| 57 | 5 |
| 58 | 7 |
| 59 | 5 |
| 60 | -1 |
| 61 | 6 |
| 62 | 6 |
| 63 | -1 |
| 64 | 8 |
| 65 | 6 |
| 66 | 5 |
| 67 | 7 |
| 68 | 6 |
| 69 | 7 |
| 70 | 6 |
| 71 | -1 |
| 72 | 6 |
| 73 | 6 |
| 74 | 7 |
| 75 | 5 |
| 76 | 6 |
| 77 | 6 |
| 78 | 7 |
| 79 | -1 |
| 80 | 8 |
| 81 | 6 |
| 82 | 8 |
[0,1,1,1,2,2,2,-1,2,2,3,3,2,3,3,-1,4,3,3,3,4,4,3, -1,4,4,4,3,-1,4,5,-1,4,4,4,5,4,6,5,-1,6,4,5,5,6,5, 6,-1,4,6,5,5,6,6,5,-1,6,5,7,5,-1,6,6,-1,8,6,5,7,6, 7,6,-1,6,6,7,5,6,6,7,-1,8,6,8] |