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 | 1 |
| 2 | 12 |
| 3 | 6 |
| 4 | 120 |
| 5 | 120 |
| 6 | 280 |
| 7 | 140 |
| 8 | 5040 |
| 9 | 5040 |
| 10 | 55440 |
| 11 | 55440 |
| 12 | 720720 |
| 13 | 720720 |
| 14 | 720720 |
| 15 | 360360 |
| 16 | 24504480 |
| 17 | 24504480 |
| 18 | 155195040 |
| 19 | 155195040 |
| 20 | 31039008 |
| 21 | 10346336 |
| 22 | 237965728 |
| 23 | 713897184 |
| 24 | 17847429600 |
| 25 | 17847429600 |
| 26 | 160626866400 |
| 27 | 22946695200 |