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