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 | -48 |
| 2 | 1344 |
| 3 | -24576 |
| 4 | 218112 |
| 5 | -688128 |
| 6 | 926416896 |
| 7 | -95932121088 |
| 8 | 5186228846592 |
| 9 | -154060166529024 |
| 10 | 1455620351852544 |
| 11 | -29436202608230400 |
| 12 | 17834604768232734720 |
| 13 | -1968810407797802926080 |
| 14 | 114581075578951670169600 |
| 15 | -3629224301781687956668416 |
| 16 | 33517817437575659447648256 |
| 17 | -1040884075746436707891806208 |