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 | -8 |
| 3 | -17 |
| 4 | 55 |
| 5 | 208 |
| 6 | -287 |
| 7 | -2159 |
| 8 | 424 |
| 9 | 19855 |
| 10 | 16039 |
| 11 | -162656 |
| 12 | -307007 |
| 13 | 1156897 |
| 14 | 3919960 |
| 15 | -6492113 |
| 16 | -41771753 |
| 17 | 16657264 |
| 18 | 392603041 |
| 19 | 242687665 |
| 20 | -3290739704 |
| 21 | -5474928689 |
| 22 | 24141728647 |
| 23 | 73416086848 |
| 24 | -143859470975 |
| 25 | -804604252607 |