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 | -6 |
| 2 | -6 |
| 3 | 498 |
| 4 | 2010 |
| 5 | -163806 |
| 6 | -1426326 |
| 7 | 113319858 |
| 8 | 1731433530 |
| 9 | -133040247486 |
| 10 | -3200805321846 |
| 11 | 235719742497618 |
| 12 | 8363215587567450 |
| 13 | -584103976037953566 |
| 14 | -29313609779751086166 |
| 15 | 1917198413998763777778 |