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 | 4 |
| 2 | 24 |
| 3 | 180 |
| 4 | 2100 |
| 5 | 27720 |
| 6 | 480480 |
| 7 | 9189180 |
| 8 | 213393180 |
| 9 | 6246600360 |
| 10 | 194090796900 |
| 11 | 7220177644680 |
| 12 | 296829525392400 |
| 13 | 12778511068142820 |
| 14 | 601807021256821380 |
| 15 | 31974268694601553320 |
| 16 | 1890171191677022594340 |
| 17 | 115365621009252758344200 |
| 18 | 7741033169720860084895820 |