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 | 299777 |
| 2 | 299977 |
| 3 | 29999777 |
| 4 | 299999977 |
| 5 | 2999999777 |
| 6 | 299999999777 |
| 7 | 2999977777777 |
| 8 | 299999999999977 |
| 9 | 2999999999977777777 |
| 10 | 2999999999999999977 |
| 11 | 299999999999977777777 |
| 12 | 299999999999999999977 |
| 13 | 2999999999999999777777 |