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 | 2 |
| 1 | 24 |
| 2 | 300 |
| 3 | 3920 |
| 4 | 52920 |
| 5 | 731808 |
| 6 | 10306296 |
| 7 | 147232800 |
| 8 | 2127513960 |
| 9 | 31031617760 |
| 10 | 456164781072 |
| 11 | 6749962774464 |
| 12 | 100445874620000 |
| 13 | 1502052155856000 |
| 14 | 22557604697766000 |
| 15 | 340044833169460800 |
| 16 | 5143178101688094600 |