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 | 3 |
| 2 | 24 |
| 3 | 1 |
| 4 | 2160 |
| 5 | 1 |
| 6 | 120960 |
| 7 | 1 |
| 8 | 6048000 |
| 9 | 1 |
| 10 | 287400960 |
| 11 | 1 |
| 12 | 9153720576000 |
| 13 | 1 |
| 14 | 597793996800 |
| 15 | 1 |
| 16 | 96035605585920000 |
| 17 | 1 |
| 18 | 51090942171709440000 |
| 19 | 1 |
| 20 | 8831434289681203200000 |
| 21 | 1 |
| 22 | 169213200472701665280000 |
| 23 | 1 |
| 24 | 22019713777512667702886400000 |
| 25 | 1 |
| 26 | 2605883287279605645312000000 |