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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | 0 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 3 |
| 9 | -1 |
| 10 | 1 |
| 11 | 2 |
| 12 | 13 |
| 13 | 17 |
| 14 | 1 |
| 15 | 1 |
| 16 | 3 |
| 17 | 31 |
| 18 | 173 |
| 19 | 169 |
| 20 | -1 |
| 21 | 1 |
| 22 | 4 |
| 23 | 57 |
| 24 | 629 |
| 25 | 3321 |
| 26 | 2079 |
| 27 | 1 |
| 28 | 1 |
| 29 | 5 |
| 30 | 91 |
| 31 | 1547 |
| 32 | 18025 |
| 33 | 81529 |
| 34 | 31261 |
| 35 | -1 |
| 36 | 1 |
| 37 | 6 |
| 38 | 133 |
| 39 | 3089 |
| 40 | 58993 |
| 41 | 662639 |
| 42 | 2443333 |
| 43 | 554483 |
| 44 | 1 |
| 45 | 1 |
| 46 | 7 |
| 47 | 183 |
| 48 | 5417 |
| 49 | 147081 |
| 50 | 2888979 |
| 51 | 29752957 |
| 52 | 86475493 |
| 53 | 11336753 |
| 54 | -1 |
[1,1,-1,1,0,1,1,1,3,-1,1,2,13,17,1,1,3,31,173,169, -1,1,4,57,629,3321,2079,1,1,5,91,1547,18025,81529, 31261,-1,1,6,133,3089,58993,662639,2443333,554483, 1,1,7,183,5417,147081,2888979,29752957,86475493, 11336753,-1] |