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 | -7 |
| 2 | 14 |
| 3 | -7 |
| 4 | 49 |
| 5 | -203 |
| 6 | 217 |
| 7 | -295 |
| 8 | 1365 |
| 9 | -2667 |
| 10 | 4214 |
| 11 | -8519 |
| 12 | 16842 |
| 13 | -38570 |
| 14 | 69012 |
| 15 | -104433 |
| 16 | 240758 |
| 17 | -493374 |
| 18 | 786835 |
| 19 | -1434601 |
| 20 | 2842567 |
| 21 | -5272206 |
| 22 | 9205546 |
| 23 | -16034312 |
| 24 | 29916572 |
| 25 | -55466005 |
| 26 | 95595395 |
| 27 | -163656780 |