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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 63 |
| 2 | 693 |
| 3 | 6993 |
| 4 | 69993 |
| 5 | 699993 |
| 6 | 6999993 |
| 7 | 69999993 |
| 8 | 699999993 |
| 9 | 6999999993 |
| 10 | 69999999993 |
| 11 | 699999999993 |
| 12 | 6999999999993 |
| 13 | 69999999999993 |
| 14 | 699999999999993 |
| 15 | 6999999999999993 |
| 16 | 69999999999999993 |
| 17 | 699999999999999993 |
| 18 | 6999999999999999993 |
| 19 | 69999999999999999993 |
| 20 | 699999999999999999993 |
[0,63,693,6993,69993,699993,6999993,69999993, 699999993,6999999993,69999999993,699999999993, 6999999999993,69999999999993,699999999999993, 6999999999999993,69999999999999993, 699999999999999993,6999999999999999993, 69999999999999999993,699999999999999999993] |