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 | 0 |
| 2 | 12 |
| 3 | -336 |
| 4 | -2096 |
| 5 | -1043328 |
| 6 | -29488704 |
| 7 | -8894706432 |
| 8 | -389860902656 |
| 9 | -170568226222080 |
| 10 | -6327905330549760 |
| 11 | -6080018829202427904 |
| 12 | 242897035394043301888 |
| 13 | -323994054628796940582912 |
| 14 | 123697309877515731773669376 |
| 15 | -13142696592417683099946516480 |