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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2025 |
| 2 | 24502500 |
| 3 | 249500250000 |
| 4 | 2499500025000000 |
| 5 | 24999500002500000000 |
| 6 | 249999500000250000000000 |
| 7 | 2499999500000025000000000000 |
| 8 | 24999999500000002500000000000000 |
| 9 | 249999999500000000250000000000000000 |
| 10 | 2499999999500000000025000000000000000000 |
[0,2025,24502500,249500250000,2499500025000000, 24999500002500000000,249999500000250000000000, 2499999500000025000000000000, 24999999500000002500000000000000, 249999999500000000250000000000000000, 2499999999500000000025000000000000000000] |