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 | -27 |
| 2 | 351 |
| 3 | -2952 |
| 4 | 18279 |
| 5 | -90234 |
| 6 | 376065 |
| 7 | -1380861 |
| 8 | 4603419 |
| 9 | -14211732 |
| 10 | 41168493 |
| 11 | -112989411 |
| 12 | 296067411 |
| 13 | -745157691 |
| 14 | 1809973404 |
| 15 | -4259279106 |
| 16 | 9741879531 |
| 17 | -21715736634 |
| 18 | 47285714262 |
| 19 | -100777640049 |
| 20 | 210581729640 |
| 21 | -432065248731 |
| 22 | 871606288422 |
| 23 | -1730764207107 |
| 24 | 3386501241606 |