This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 97 |
| 3 | 977 |
| 4 | 7877 |
| 5 | 97777 |
| 6 | 787777 |
| 7 | 7877777 |
| 8 | 77767777 |
| 9 | 787777777 |
| 10 | 8777777777 |
| 11 | 79777777777 |
| 12 | 777777779777 |
| 13 | 7877777777777 |
| 14 | 77777779777777 |
| 15 | 778777777777777 |
| 16 | 8777777777777777 |
| 17 | 77797777777777777 |
| 18 | 797777777777777777 |