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| n | a(n) |
|---|---|
| 1 | 11 |
| 2 | 1221 |
| 3 | 123321 |
| 4 | 12344321 |
| 5 | 1234554321 |
| 6 | 123456654321 |
| 7 | 12345677654321 |
| 8 | 1234567887654321 |
| 9 | 123456789987654321 |
| 10 | 1234567891010987654321 |
| 11 | 12345678910111110987654321 |
| 12 | 123456789101112121110987654321 |
[11,1221,123321,12344321,1234554321,123456654321, 12345677654321,1234567887654321, 123456789987654321,1234567891010987654321, 12345678910111110987654321, 123456789101112121110987654321] |