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 | 0 |
| 1 | 1 |
| 2 | 8 |
| 3 | 76 |
| 4 | -2752 |
| 5 | -553904 |
| 6 | -77878912 |
| 7 | -11370511424 |
| 8 | -1778864822272 |
| 9 | -282582967817984 |
| 10 | -36606453394757632 |
| 11 | 2075368674171759616 |
| 12 | 5791517230149348343808 |
| 13 | 4398620127304280971595776 |