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| n | a(n) |
|---|---|
| 1 | 49 |
| 2 | 409 |
| 3 | 4009 |
| 4 | 40009 |
| 5 | 400009 |
| 6 | 4000009 |
| 7 | 40000009 |
| 8 | 400000009 |
| 9 | 4000000009 |
| 10 | 40000000009 |
| 11 | 400000000009 |
| 12 | 4000000000009 |
| 13 | 40000000000009 |
| 14 | 400000000000009 |
| 15 | 4000000000000009 |
| 16 | 40000000000000009 |
| 17 | 400000000000000009 |
| 18 | 4000000000000000009 |
| 19 | 40000000000000000009 |
| 20 | 400000000000000000009 |
| 21 | 4000000000000000000009 |
[49,409,4009,40009,400009,4000009,40000009, 400000009,4000000009,40000000009,400000000009, 4000000000009,40000000000009,400000000000009, 4000000000000009,40000000000000009, 400000000000000009,4000000000000000009, 40000000000000000009,400000000000000000009, 4000000000000000000009] |