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 | 3 |
| 2 | 55 |
| 3 | 5735537337753 |
| 4 | 53737577757753 |
| 5 | 335355753333373553355 |
| 6 | 573535753575353335777335733757755 |
| 7 | 7357333757773777355335733737733553753 |