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 | -19 |
| 2 | 171 |
| 3 | -988 |
| 4 | 4237 |
| 5 | -14896 |
| 6 | 46075 |
| 7 | -130549 |
| 8 | 344888 |
| 9 | -858325 |
| 10 | 2032924 |
| 11 | -4621313 |
| 12 | 10137716 |
| 13 | -21545639 |
| 14 | 44525987 |
| 15 | -89757843 |
| 16 | 176925625 |
| 17 | -341688495 |
| 18 | 647687314 |
| 19 | -1206921212 |
| 20 | 2213842874 |
| 21 | -4001882220 |
| 22 | 7136374179 |