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 | 1 |
| 2 | 4 |
| 3 | 24 |
| 4 | 48 |
| 5 | 4320 |
| 6 | 8640 |
| 7 | 120960 |
| 8 | 3628800 |
| 9 | 7257600 |
| 10 | 14515200 |
| 11 | 6706022400 |
| 12 | 13412044800 |
| 13 | 8717829120000 |
| 14 | 470762772480000 |
| 15 | 941525544960000 |
| 16 | 1883051089920000 |
| 17 | 2112783322890240000 |
| 18 | 147894832602316800000 |