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) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | 1968 |
| 3 | 16467840 |
| 4 | 554765137920 |
| 5 | 52485654509568000 |
| 6 | 11281219212469764096000 |
| 7 | 4790353998374876546334720000 |
| 8 | 3639616082290561423547931033600000 |