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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 4 |
| 4 | -1 |
| 5 | 1 |
| 6 | 9 |
| 7 | -1 |
| 8 | 1 |
| 9 | 5 |
| 10 | 16 |
| 11 | -1 |
| 12 | 1 |
| 13 | 5 |
| 14 | 11 |
| 15 | 25 |
| 16 | -1 |
| 17 | 1 |
| 18 | 5 |
| 19 | 11 |
| 20 | 19 |
| 21 | 36 |
| 22 | -1 |
| 23 | 1 |
| 24 | 5 |
| 25 | 11 |
| 26 | 19 |
| 27 | 29 |
| 28 | 49 |
| 29 | -1 |
| 30 | 1 |
| 31 | 5 |
| 32 | 11 |
| 33 | 19 |
| 34 | 29 |
| 35 | 41 |
| 36 | 64 |
| 37 | -1 |
| 38 | 1 |
| 39 | 5 |
| 40 | 11 |
| 41 | 19 |
| 42 | 29 |
| 43 | 41 |
| 44 | 55 |
| 45 | 81 |
| 46 | -1 |
| 47 | 1 |
| 48 | 5 |
| 49 | 11 |
| 50 | 19 |
| 51 | 29 |
| 52 | 41 |
| 53 | 55 |
| 54 | 71 |
| 55 | 100 |
[1,-1,4,-1,1,9,-1,1,5,16,-1,1,5,11,25,-1,1,5,11, 19,36,-1,1,5,11,19,29,49,-1,1,5,11,19,29,41,64,-1, 1,5,11,19,29,41,55,81,-1,1,5,11,19,29,41,55,71, 100] |