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 | 24 |
| 3 | 580 |
| 4 | 21420 |
| 5 | 1068480 |
| 6 | 67189248 |
| 7 | 5098406400 |
| 8 | 453030209280 |
| 9 | 46120247659200 |
| 10 | 5290918350734016 |
| 11 | 675157532791996800 |
| 12 | 94836990558591590400 |
| 13 | 14538639675855504384000 |
| 14 | 2415072877848471727687680 |