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 | 15 |
| 3 | 207 |
| 4 | 24777 |
| 5 | 1797835772 |
| 6 | 2401072239422894903 |
| 7 | 36947191921380265723491992928675837908 |
| 8 | 1242004943621920150072266455052958650167034792376067355585774287542963919184 |