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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 221 |
| 3 | 333221 |
| 4 | 4444333221 |
| 5 | 555554444333221 |
| 6 | 666666555554444333221 |
| 7 | 7777777666666555554444333221 |
| 8 | 888888887777777666666555554444333221 |
| 9 | 999999999888888887777777666666555554444333221 |
| 10 | 10101010101010101010999999999888888887777777666666555554444333221 |
[1,221,333221,4444333221,555554444333221, 666666555554444333221, 7777777666666555554444333221, 888888887777777666666555554444333221, 999999999888888887777777666666555554444333221, 10101010101010101010999999999888888887777777666666\ 555554444333221] |