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 | 1 |
| 1 | 2 |
| 2 | 16 |
| 3 | 416 |
| 4 | 33280 |
| 5 | 8053760 |
| 6 | 5863137280 |
| 7 | 12816818094080 |
| 8 | 84078326697164800 |
| 9 | 1654829626053597593600 |
| 10 | 97714379759212830706892800 |
| 11 | 17309711516825516108403231948800 |