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 | 0 |
| 2 | 9 |
| 3 | 656 |
| 4 | 643204 |
| 5 | 4235650596 |
| 6 | 259039174953636 |