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 | 389 |
| 2 | 401 |
| 3 | 641 |
| 4 | 65921 |
| 5 | 4294967681 |
| 6 | 340282366920938463463374607431768211841 |