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 | 4 |
| 2 | 12 |
| 3 | 36 |
| 4 | 180 |
| 5 | 1260 |
| 6 | 252 |
| 7 | 252 |
| 8 | 2772 |
| 9 | 69300 |
| 10 | 900900 |
| 11 | 900900 |
| 12 | 15315300 |
| 13 | 15315300 |
| 14 | 290990700 |
| 15 | 290990700 |
| 16 | 6692786100 |
| 17 | 46849502700 |
| 18 | 46849502700 |
| 19 | 46849502700 |
| 20 | 46849502700 |
| 21 | 1358635578300 |
| 22 | 42117702927300 |
| 23 | 42117702927300 |
| 24 | 42117702927300 |