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 | 2 |
| 3 | 24 |
| 4 | 13440 |
| 5 | 1009008000 |
| 6 | 19947543780003840 |
| 7 | 170891375144777551827763200 |
| 8 | 942542805268120269309770939139883008000 |
| 9 | 4650425326497486529782791149613966242353671284224000000 |