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 | -1 |
| 2 | 3 |
| 3 | 6 |
| 4 | -8 |
| 5 | -501 |
| 6 | -13623 |
| 7 | -409953 |
| 8 | -14544683 |
| 9 | -607055209 |
| 10 | -29421219966 |
| 11 | -1632715832341 |
| 12 | -102423931253271 |
| 13 | -7182065357683744 |
| 14 | -557479490745141406 |
| 15 | -47499193522110824640 |
| 16 | -4410100445892863617679 |
| 17 | -443346294340660384160358 |