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