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| n | a(n) |
|---|---|
| 1 | 111 |
| 2 | 1221 |
| 3 | 13331 |
| 4 | 144441 |
| 5 | 1555551 |
| 6 | 16666661 |
| 7 | 177777771 |
| 8 | 1888888881 |
| 9 | 19999999991 |
| 10 | 1101010101010101010101 |
| 11 | 111111111111111111111111 |
| 12 | 11212121212121212121212121 |
| 13 | 1131313131313131313131313131 |
| 14 | 114141414141414141414141414141 |
| 15 | 11515151515151515151515151515151 |
[111,1221,13331,144441,1555551,16666661,177777771, 1888888881,19999999991,1101010101010101010101, 111111111111111111111111, 11212121212121212121212121, 1131313131313131313131313131, 114141414141414141414141414141, 11515151515151515151515151515151] |