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 | 24 |
| 4 | 720 |
| 5 | 2520 |
| 6 | 120960 |
| 7 | 259459200 |
| 8 | 1357171200 |
| 9 | 4929724800 |
| 10 | 42608389824000 |
| 11 | 11912739135897600 |
| 12 | 59907396092544000 |
| 13 | 20458385028297216000 |
| 14 | 7926428532945162240000 |
| 15 | 4693751193479184764928000 |
| 16 | 328774885640356760904499200000 |
| 17 | 12797917159224592605450240000 |