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 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 5760 |
| 7 | 766080 |
| 8 | 149022720 |
| 9 | 48990251520 |
| 10 | 28928242022400 |
| 11 | 32147584690636800 |
| 12 | 69035206021583155200 |