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 | 2 |
| 2 | -5 |
| 3 | -35 |
| 4 | -435 |
| 5 | -87986 |
| 6 | -7186995 |
| 7 | -496722800 |
| 8 | -68316404507 |
| 9 | -9102428703537 |
| 10 | -3721326642272925 |
| 11 | -488684390484513105 |
| 12 | -195315251884652232704 |