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 | 2 |
| 3 | 24 |
| 4 | 744 |
| 5 | 35160 |
| 6 | 2394720 |
| 7 | 222712560 |
| 8 | 27154350720 |
| 9 | 4205374225920 |
| 10 | 806700010233600 |
| 11 | 187793061031699200 |
| 12 | 52162131258836121600 |
| 13 | 17043501717850146739200 |
| 14 | 6471785359791584459827200 |
| 15 | 2826261760629911644744704000 |
| 16 | 1406604814631643298586923008000 |