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 | 0 |
| 3 | 787 |
| 4 | 7877 |
| 5 | 78787 |
| 6 | 777787 |
| 7 | 7778777 |
| 8 | 77778887 |
| 9 | 777788887 |
| 10 | 7777778887 |
| 11 | 77777778887 |
| 12 | 777777777877 |
| 13 | 7777777787777 |
| 14 | 77777777778787 |
| 15 | 777777777777787 |
| 16 | 7777777778788777 |
| 17 | 77777777777778887 |
| 18 | 777777777787878887 |