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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 7 |
| 5 | 23 |
| 6 | 223 |
| 7 | 227 |
| 8 | 337 |
| 9 | 557 |
| 10 | 577 |
| 11 | 2333 |
| 12 | 2357 |
| 13 | 2377 |
| 14 | 2557 |
| 15 | 2777 |
| 16 | 33377 |
| 17 | 222337 |
| 18 | 222557 |
| 19 | 233357 |
| 20 | 233777 |
| 21 | 235577 |
| 22 | 2222333 |
| 23 | 2233337 |
| 24 | 2235557 |
| 25 | 3337777 |
| 26 | 3355777 |
| 27 | 5555777 |
| 28 | 22222223 |
| 29 | 22233577 |
| 30 | 23333357 |
| 31 | 23377777 |
| 32 | 25577777 |
| 33 | 222222227 |
| 34 | 222222557 |
| 35 | 222222577 |
[2,3,5,7,23,223,227,337,557,577,2333,2357,2377, 2557,2777,33377,222337,222557,233357,233777, 235577,2222333,2233337,2235557,3337777,3355777, 5555777,22222223,22233577,23333357,23377777, 25577777,222222227,222222557,222222577] |