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) |
|---|---|
| 2 | 1 |
| 3 | 0 |
| 4 | 6 |
| 5 | 68 |
| 6 | 6102 |
| 7 | 1404416 |
| 8 | 1094802826 |
| 9 | 2524252113468 |