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) |
|---|---|
| 1 | -1 |
| 2 | 1 |
| 3 | -1 |
| 4 | 2 |
| 5 | -2 |
| 6 | 4 |
| 7 | -4 |
| 8 | 7 |
| 9 | -7 |
| 10 | 12 |
| 11 | -12 |
| 12 | 22 |
| 13 | -21 |
| 14 | 39 |
| 15 | -39 |
| 16 | 68 |
| 17 | -70 |
| 18 | 119 |
| 19 | -127 |
| 20 | 210 |
| 21 | -229 |
| 22 | 369 |
| 23 | -413 |
| 24 | 649 |
| 25 | -742 |
| 26 | 1143 |
| 27 | -1334 |
| 28 | 2017 |
| 29 | -2393 |
| 30 | 3561 |
| 31 | -4289 |
| 32 | 6293 |
| 33 | -7680 |
| 34 | 11129 |
| 35 | -13739 |
| 36 | 19696 |
| 37 | -24559 |
| 38 | 34879 |
| 39 | -43871 |
| 40 | 61801 |
| 41 | -78324 |
| 42 | 109555 |
| 43 | -139764 |
| 44 | 194291 |
| 45 | -249295 |
| 46 | 344694 |
| 47 | -444496 |
| 48 | 611723 |
| 49 | -792285 |