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 | 0 |
| 2 | 4 |
| 3 | 252 |
| 4 | 2112 |
| 5 | 2772 |
| 6 | 6336 |
| 7 | 21012 |
| 8 | 27072 |
| 9 | 42924 |
| 10 | 48384 |
| 11 | 48984 |
| 12 | 63036 |
| 13 | 252252 |
| 14 | 297792 |
| 15 | 407704 |
| 16 | 2327232 |
| 17 | 2572752 |
| 18 | 2747472 |
| 19 | 2774772 |
| 20 | 2958592 |
| 21 | 4457544 |
| 22 | 4811184 |
| 23 | 6378736 |
| 24 | 6396936 |
| 25 | 25777752 |
| 26 | 27633672 |
| 27 | 29344392 |
| 28 | 63099036 |
| 29 | 63399336 |
| 30 | 404080404 |
| 31 | 409757904 |
| 32 | 441525144 |