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 | 2 |
| 2 | 24 |
| 3 | 20922789888000 |
| 4 | 2432902008176640000 |
| 5 | 25852016738884976640000 |
| 6 | 265252859812191058636308480000000 |
| 7 | 263130836933693530167218012160000000 |