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| n | a(n) |
|---|---|
| 0 | -1 |
| 1 | -1 |
| 2 | -1 |
| 3 | -1 |
| 4 | 2 |
| 5 | -1 |
| 6 | -1 |
| 7 | 3 |
| 8 | 3 |
| 9 | -1 |
| 10 | -1 |
| 11 | 4 |
| 12 | 14 |
| 13 | 4 |
| 14 | -1 |
| 15 | -1 |
| 16 | 5 |
| 17 | 17 |
| 18 | 17 |
| 19 | 5 |
| 20 | -1 |
| 21 | -1 |
| 22 | 6 |
| 23 | 20 |
| 24 | 41 |
| 25 | 20 |
| 26 | 6 |
| 27 | -1 |
| 28 | -1 |
| 29 | 7 |
| 30 | 23 |
| 31 | 47 |
| 32 | 47 |
| 33 | 23 |
| 34 | 7 |
| 35 | -1 |
| 36 | -1 |
| 37 | 8 |
| 38 | 26 |
| 39 | 53 |
| 40 | 89 |
| 41 | 53 |
| 42 | 26 |
| 43 | 8 |
| 44 | -1 |
| 45 | -1 |
| 46 | 9 |
| 47 | 29 |
| 48 | 59 |
| 49 | 99 |
| 50 | 99 |
| 51 | 59 |
| 52 | 29 |
| 53 | 9 |
| 54 | -1 |
| 55 | -1 |
| 56 | 10 |
| 57 | 32 |
| 58 | 65 |
| 59 | 109 |
| 60 | 164 |
| 61 | 109 |
| 62 | 65 |
| 63 | 32 |
| 64 | 10 |
| 65 | -1 |
[-1,-1,-1,-1,2,-1,-1,3,3,-1,-1,4,14,4,-1,-1,5,17, 17,5,-1,-1,6,20,41,20,6,-1,-1,7,23,47,47,23,7,-1, -1,8,26,53,89,53,26,8,-1,-1,9,29,59,99,99,59,29,9, -1,-1,10,32,65,109,164,109,65,32,10,-1] |