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) |
|---|---|
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 9 |
| 8 | 43 |
| 9 | 655 |
| 10 | 42426 |
| 11 | 11590894 |
| 12 | 12561206794 |