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) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 130 |
| 3 | 44739500 |
| 4 | 4611686018516874838 |
| 5 | 8507059173023461595807737228465099196 |
| 6 | 17552048611426197782986337964292523732529439672780432120964458900 |