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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 33 |
| 3 | 555 |
| 4 | 7777 |
| 5 | 122221 |
| 6 | 1444443 |
| 7 | 18888887 |
| 8 | 211111109 |
| 9 | 2555555553 |
| 10 | 32222222219 |
| 11 | 344444444441 |
| 12 | 4111111111107 |
| 13 | 45555555555551 |
| 14 | 477777777777773 |
| 15 | 5222222222222217 |
| 16 | 58888888888888883 |
| 17 | 655555555555555549 |
| 18 | 6777777777777777771 |
| 19 | 74444444444444444437 |
| 20 | 788888888888888888881 |
[2,33,555,7777,122221,1444443,18888887,211111109, 2555555553,32222222219,344444444441,4111111111107, 45555555555551,477777777777773,5222222222222217, 58888888888888883,655555555555555549, 6777777777777777771,74444444444444444437, 788888888888888888881] |