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 | 1 |
| 3 | 5 |
| 4 | 65 |
| 5 | 3753 |
| 6 | 860017 |
| 7 | 839301197 |
| 8 | 3535646416019 |
| 9 | 65638445025610187 |
| 10 | 5443595184898837903553 |