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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 7 |
| 3 | 227 |
| 4 | 277 |
| 5 | 727 |
| 6 | 787 |
| 7 | 827 |
| 8 | 877 |
| 9 | 887 |
| 10 | 2287 |
| 11 | 2777 |
| 12 | 2887 |
| 13 | 7727 |
| 14 | 7877 |
| 15 | 8287 |
| 16 | 8887 |
| 17 | 22277 |
| 18 | 22727 |
| 19 | 22777 |
| 20 | 22787 |
| 21 | 22877 |
| 22 | 27277 |
| 23 | 27827 |
| 24 | 28277 |
| 25 | 72227 |
| 26 | 72277 |
| 27 | 72287 |
| 28 | 72727 |
| 29 | 78277 |
| 30 | 78787 |
| 31 | 78877 |
| 32 | 78887 |
| 33 | 82727 |
| 34 | 82787 |
| 35 | 87277 |
| 36 | 87877 |
| 37 | 87887 |
| 38 | 222787 |
| 39 | 222877 |
| 40 | 227827 |
| 41 | 228887 |
[2,7,227,277,727,787,827,877,887,2287,2777,2887, 7727,7877,8287,8887,22277,22727,22777,22787,22877, 27277,27827,28277,72227,72277,72287,72727,78277, 78787,78877,78887,82727,82787,87277,87877,87887, 222787,222877,227827,228887] |