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 | -30 |
| 1 | 1827 |
| 2 | -75915 |
| 3 | 2774695 |
| 4 | -97362265 |
| 5 | 3410657250 |
| 6 | -121647896370 |
| 7 | 4464233824050 |
| 8 | -169525943987400 |
| 9 | 6681570663692925 |
| 10 | -273715584240223125 |
| 11 | 11660420923428902625 |
| 12 | -516518847915111916875 |
| 13 | 23780637468174359272500 |
| 14 | -1137205925185934836732500 |