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 | 4 |
| 2 | 24 |
| 3 | 480 |
| 4 | 130560 |
| 5 | 8589803520 |
| 6 | 36893488138829168640 |
| 7 | 680564733841876926889855726716117319680 |
| 8 | 231584178474632390847141970017375815705859404597439251151988418800962722856960 |