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 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 24 |
| 4 | 384 |
| 5 | 5120 |
| 6 | 61440 |
| 7 | 688128 |
| 8 | 7340032 |
| 9 | 75497472 |
| 10 | 754974720 |
| 11 | 7381975040 |
| 12 | 70866960384 |
| 13 | 670014898176 |
| 14 | 6253472382976 |
| 15 | 57724360458240 |
| 16 | 527765581332480 |
| 17 | 4785074604081152 |
| 18 | 43065671436730368 |
| 19 | 385057768140177408 |