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| n | a(n) |
|---|---|
| 1 | 37 |
| 2 | 73 |
| 3 | 33373777 |
| 4 | 33773737 |
| 5 | 37373773 |
| 6 | 37377337 |
| 7 | 73337377 |
| 8 | 73337773 |
| 9 | 73373737 |
| 10 | 73773373 |
| 11 | 77337373 |
| 12 | 77733373 |
| 13 | 3337737737 |
| 14 | 3337777337 |
| 15 | 3377733773 |
| 16 | 3733377377 |
| 17 | 3733733777 |
| 18 | 3737733773 |
| 19 | 3773333777 |
| 20 | 3773337377 |
| 21 | 3773733737 |
| 22 | 3777333773 |
| 23 | 3777337337 |
| 24 | 3777337373 |
[37,73,33373777,33773737,37373773,37377337, 73337377,73337773,73373737,73773373,77337373, 77733373,3337737737,3337777337,3377733773, 3733377377,3733733777,3737733773,3773333777, 3773337377,3773733737,3777333773,3777337337, 3777337373] |