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 | 2 |
| 2 | -18 |
| 3 | 270 |
| 4 | -4902 |
| 5 | 98538 |
| 6 | -2110794 |
| 7 | 47227846 |
| 8 | -1090742094 |
| 9 | 25806364434 |
| 10 | -622267199554 |
| 11 | 15236456140542 |
| 12 | -377814588773622 |
| 13 | 9468373002766074 |
| 14 | -239434464005544570 |
| 15 | 6101951612867546166 |
| 16 | -156561081975745809566 |
| 17 | 4040863076496835880226 |