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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 11 |
| 4 | 5 |
| 5 | 29 |
| 6 | 7 |
| 7 | -1 |
| 8 | 71 |
| 9 | 89 |
| 10 | 11 |
| 11 | 131 |
| 12 | 13 |
| 13 | 181 |
| 14 | -1 |
| 15 | 239 |
| 16 | 17 |
| 17 | 5167 |
| 18 | 19 |
| 19 | 379 |
| 20 | 419 |
| 21 | 461 |
| 22 | 23 |
| 23 | -1 |
| 24 | 599 |
| 25 | 251894449 |
| 26 | 701 |
| 27 | 20357 |
| 28 | 29 |
| 29 | 25171 |
| 30 | 31 |
| 31 | 991 |
| 32 | 36002209323169 |
| 33 | 47468744103199 |
| 34 | -1 |
| 35 | 1259 |
| 36 | 37 |
| 37 | 2625505273 |
| 38 | 1481 |
| 39 | 1559 |
| 40 | 41 |
| 41 | 1721 |
| 42 | 43 |
| 43 | 150103799 |
| 44 | 1979 |
| 45 | 2069 |
| 46 | 47 |
| 47 | -1 |
| 48 | 2351 |
| 49 | 287762399 |
[2,3,11,5,29,7,-1,71,89,11,131,13,181,-1,239,17, 5167,19,379,419,461,23,-1,599,251894449,701,20357, 29,25171,31,991,36002209323169,47468744103199,-1, 1259,37,2625505273,1481,1559,41,1721,43,150103799, 1979,2069,47,-1,2351,287762399] |