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 | 1 |
| 2 | 2 |
| 3 | 40 |
| 4 | 815 |
| 5 | 22320 |
| 6 | 352181 |
| 7 | 8549705 |
| 8 | 286833177 |