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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 30 |
| 3 | 300 |
| 4 | 3000 |
| 5 | 30000 |
| 6 | 300000 |
| 7 | 3000000 |
| 8 | 30000000 |
| 9 | 300000000 |
| 10 | 3000000000 |
| 11 | 30000000000 |
| 12 | 300000000000 |
| 13 | 3000000000000 |
| 14 | 30000000000000 |
| 15 | 300000000000000 |
| 16 | 3000000000000000 |
| 17 | 30000000000000000 |
| 18 | 300000000000000000 |
| 19 | 3000000000000000000 |
| 20 | 30000000000000000000 |
| 21 | 300000000000000000000 |
[1,3,30,300,3000,30000,300000,3000000,30000000, 300000000,3000000000,30000000000,300000000000, 3000000000000,30000000000000,300000000000000, 3000000000000000,30000000000000000, 300000000000000000,3000000000000000000, 30000000000000000000,300000000000000000000] |