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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 7 |
| 5 | 22 |
| 6 | 33 |
| 7 | 55 |
| 8 | 77 |
| 9 | 222 |
| 10 | 333 |
| 11 | 555 |
| 12 | 735 |
| 13 | 777 |
| 14 | 2222 |
| 15 | 2232 |
| 16 | 2322 |
| 17 | 2772 |
| 18 | 3222 |
| 19 | 3333 |
| 20 | 3555 |
| 21 | 5355 |
| 22 | 5535 |
| 23 | 5555 |
| 24 | 5775 |
| 25 | 7777 |
| 26 | 22222 |
| 27 | 22332 |
| 28 | 22722 |
| 29 | 23232 |
| 30 | 23322 |
| 31 | 23772 |
| 32 | 27272 |
| 33 | 32232 |
| 34 | 32322 |
| 35 | 33222 |
| 36 | 33333 |
| 37 | 33555 |
| 38 | 35355 |
| 39 | 35535 |
| 40 | 37737 |
| 41 | 53355 |
| 42 | 53535 |
[2,3,5,7,22,33,55,77,222,333,555,735,777,2222, 2232,2322,2772,3222,3333,3555,5355,5535,5555,5775, 7777,22222,22332,22722,23232,23322,23772,27272, 32232,32322,33222,33333,33555,35355,35535,37737, 53355,53535] |