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| n | a(n) |
|---|---|
| 1 | 131 |
| 2 | 191 |
| 3 | 313 |
| 4 | 919 |
| 5 | 113111311 |
| 6 | 131333131 |
| 7 | 313111313 |
| 8 | 331333133 |
| 9 | 11199199111 |
| 10 | 99911911999 |
| 11 | 1111191911111 |
| 12 | 9999919199999 |
| 13 | 133131131131331 |
| 14 | 311313313313113 |
| 15 | 777997999799777 |
| 16 | 999779777977999 |
| 17 | 11177771717777111 |
[131,191,313,919,113111311,131333131,313111313, 331333133,11199199111,99911911999,1111191911111, 9999919199999,133131131131331,311313313313113, 777997999799777,999779777977999,11177771717777111] |