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 | -2 |
| 2 | 4 |
| 3 | -8 |
| 4 | 15 |
| 5 | -26 |
| 6 | 44 |
| 7 | -72 |
| 8 | 114 |
| 9 | -178 |
| 10 | 272 |
| 11 | -408 |
| 12 | 605 |
| 13 | -884 |
| 14 | 1276 |
| 15 | -1824 |
| 16 | 2580 |
| 17 | -3616 |
| 18 | 5028 |
| 19 | -6936 |
| 20 | 9498 |
| 21 | -12922 |
| 22 | 17468 |
| 23 | -23472 |
| 24 | 31369 |
| 25 | -41700 |
| 26 | 55156 |
| 27 | -72616 |
| 28 | 95172 |
| 29 | -124202 |
| 30 | 161436 |
| 31 | -209016 |
| 32 | 269616 |
| 33 | -346562 |
| 34 | 443952 |
| 35 | -566856 |
| 36 | 721530 |
| 37 | -915642 |
| 38 | 1158608 |