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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 77 |
| 3 | 707 |
| 4 | 717 |
| 5 | 727 |
| 6 | 737 |
| 7 | 747 |
| 8 | 757 |
| 9 | 767 |
| 10 | 777 |
| 11 | 787 |
| 12 | 797 |
| 13 | 7007 |
| 14 | 7117 |
| 15 | 7227 |
| 16 | 7337 |
| 17 | 7447 |
| 18 | 7557 |
| 19 | 7667 |
| 20 | 7777 |
| 21 | 7887 |
| 22 | 7997 |
| 23 | 70007 |
| 24 | 70107 |
| 25 | 70207 |
| 26 | 70307 |
| 27 | 70407 |
| 28 | 70507 |
| 29 | 70607 |
| 30 | 70707 |
| 31 | 70807 |
| 32 | 70907 |
| 33 | 71017 |
| 34 | 71117 |
| 35 | 71217 |
| 36 | 71317 |
| 37 | 71417 |
| 38 | 71517 |
| 39 | 71617 |
| 40 | 71717 |
| 41 | 71817 |
| 42 | 71917 |
[7,77,707,717,727,737,747,757,767,777,787,797, 7007,7117,7227,7337,7447,7557,7667,7777,7887,7997, 70007,70107,70207,70307,70407,70507,70607,70707, 70807,70907,71017,71117,71217,71317,71417,71517, 71617,71717,71817,71917] |