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 | 2 |
| 1 | 0 |
| 2 | 24 |
| 3 | -288 |
| 4 | 3744 |
| 5 | -48384 |
| 6 | 625536 |
| 7 | -8087040 |
| 8 | 104550912 |
| 9 | -1351655424 |
| 10 | 17474476032 |
| 11 | -225913577472 |
| 12 | 2920656642048 |
| 13 | -37758842634240 |
| 14 | 488153991315456 |
| 15 | -6310954007396352 |
| 16 | 81589295984541696 |
| 17 | -1054802999903256576 |
| 18 | 13636707550653579264 |