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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 7 |
| 5 | 23 |
| 6 | 37 |
| 7 | 53 |
| 8 | 73 |
| 9 | 223 |
| 10 | 233 |
| 11 | 337 |
| 12 | 353 |
| 13 | 373 |
| 14 | 523 |
| 15 | 733 |
| 16 | 773 |
| 17 | 2237 |
| 18 | 2333 |
| 19 | 3373 |
| 20 | 3533 |
| 21 | 3733 |
| 22 | 5233 |
| 23 | 5237 |
| 24 | 5323 |
| 25 | 7333 |
| 26 | 7523 |
| 27 | 23333 |
| 28 | 23773 |
| 29 | 25237 |
| 30 | 32237 |
| 31 | 33533 |
| 32 | 33773 |
| 33 | 35323 |
| 34 | 35353 |
| 35 | 37223 |
| 36 | 37337 |
| 37 | 52237 |
| 38 | 53233 |
| 39 | 53353 |
| 40 | 53773 |
| 41 | 73523 |
| 42 | 75323 |
| 43 | 77323 |
[2,3,5,7,23,37,53,73,223,233,337,353,373,523,733, 773,2237,2333,3373,3533,3733,5233,5237,5323,7333, 7523,23333,23773,25237,32237,33533,33773,35323, 35353,37223,37337,52237,53233,53353,53773,73523, 75323,77323] |