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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 11 |
| 2 | 1221 |
| 3 | 123321 |
| 4 | 12344321 |
| 5 | 1234554321 |
| 6 | 123456654321 |
| 7 | 12345677654321 |
| 8 | 1234567887654321 |
| 9 | 123456789987654321 |
| 10 | 12345679010987654321 |
| 11 | 1234567901220987654321 |
| 12 | 123456790123320987654321 |
| 13 | 12345679012344320987654321 |
| 14 | 1234567901234554320987654321 |
[0,11,1221,123321,12344321,1234554321, 123456654321,12345677654321,1234567887654321, 123456789987654321,12345679010987654321, 1234567901220987654321,123456790123320987654321, 12345679012344320987654321, 1234567901234554320987654321] |