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| n | a(n) |
|---|---|
| 1 | 40 |
| 2 | 490 |
| 3 | 4990 |
| 4 | 49990 |
| 5 | 499990 |
| 6 | 4999990 |
| 7 | 49999990 |
| 8 | 499999990 |
| 9 | 4999999990 |
| 10 | 49999999990 |
| 11 | 499999999990 |
| 12 | 4999999999990 |
| 13 | 49999999999990 |
| 14 | 499999999999990 |
| 15 | 4999999999999990 |
| 16 | 49999999999999990 |
| 17 | 499999999999999990 |
[40,490,4990,49990,499990,4999990,49999990, 499999990,4999999990,49999999990,499999999990, 4999999999990,49999999999990,499999999999990, 4999999999999990,49999999999999990, 499999999999999990] |