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 | 720 |
| 2 | 25920 |
| 3 | 979200 |
| 4 | 4680000 |
| 5 | 138297600 |
| 6 | 1056706560 |
| 7 | 1721606400 |
| 8 | 12860654400 |
| 9 | 68518981440 |
| 10 | 1095199948800 |
| 11 | 1004497044480 |
| 12 | 3057017889600 |
| 13 | 20674026236160 |
| 14 | 47607300000000 |
| 15 | 102804157834560 |
| 16 | 210103196385600 |