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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 25 |
| 3 | 252 |
| 4 | 2525 |
| 5 | 25252 |
| 6 | 252525 |
| 7 | 2525252 |
| 8 | 25252525 |
| 9 | 252525252 |
| 10 | 2525252525 |
| 11 | 25252525252 |
| 12 | 252525252525 |
| 13 | 2525252525252 |
| 14 | 25252525252525 |
| 15 | 252525252525252 |
| 16 | 2525252525252525 |
| 17 | 25252525252525252 |
| 18 | 252525252525252525 |
| 19 | 2525252525252525252 |
| 20 | 25252525252525252525 |
[2,25,252,2525,25252,252525,2525252,25252525, 252525252,2525252525,25252525252,252525252525, 2525252525252,25252525252525,252525252525252, 2525252525252525,25252525252525252, 252525252525252525,2525252525252525252, 25252525252525252525] |