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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 7 |
| 5 | 17 |
| 6 | 23 |
| 7 | 31 |
| 8 | 101 |
| 9 | 401 |
| 10 | 4657 |
| 11 | 15823 |
| 12 | 80783 |
| 13 | 139091 |
| 14 | 541061 |
| 15 | 1400251 |
| 16 | 27801973 |
| 17 | 82419121 |
| 18 | 2147261729 |
| 19 | 12554734117 |
| 20 | 16473868771 |
| 21 | 98268480059747 |
| 22 | 389987558038815689 |
| 23 | 13332015897088468423 |
| 24 | 315610157790100954828793509 |
| 25 | 21710126322471651344856594580559 |
[2,3,5,7,17,23,31,101,401,4657,15823,80783,139091, 541061,1400251,27801973,82419121,2147261729, 12554734117,16473868771,98268480059747, 389987558038815689,13332015897088468423, 315610157790100954828793509, 21710126322471651344856594580559] |