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) |
|---|---|
| 3 | 20 |
| 4 | 30 |
| 5 | 72 |
| 6 | 240 |
| 7 | 720 |
| 8 | 1620 |
| 9 | 2680 |
| 10 | 3336 |
| 11 | 2880 |
| 12 | 1280 |