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 | 135 |
| 3 | 20503125 |
| 4 | 119709242282867431640625 |
| 5 | 39709946214287663263304759568121660162631769708241336047649383544921875 |