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 | -24 |
| 3 | -74 |
| 4 | 2976 |
| 5 | 15376 |
| 6 | -906624 |
| 7 | -6563024 |
| 8 | 514546176 |
| 9 | 4789470976 |
| 10 | -469222938624 |
| 11 | -5338232282624 |
| 12 | 627559296638976 |
| 13 | 8437702651826176 |
| 14 | -1157248322241921024 |
| 15 | -17953287144063002624 |
| 16 | 2814090582404042981376 |
| 17 | 49478116534660975230976 |
| 18 | -8724885890905288434253824 |