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 | -3 |
| 2 | 2 |
| 3 | -5 |
| 4 | 17 |
| 5 | -23 |
| 6 | 43 |
| 7 | -87 |
| 8 | 178 |
| 9 | -378 |
| 10 | 700 |
| 11 | -1402 |
| 12 | 2837 |
| 13 | -5651 |
| 14 | 11295 |
| 15 | -22592 |
| 16 | 45397 |
| 17 | -90587 |
| 18 | 181187 |
| 19 | -362566 |
| 20 | 724949 |
| 21 | -1449986 |
| 22 | 2900068 |
| 23 | -5801059 |
| 24 | 11601675 |
| 25 | -23204798 |
| 26 | 46409816 |
| 27 | -92817126 |
| 28 | 185633688 |
| 29 | -371270603 |
| 30 | 742544062 |
| 31 | -1485079884 |
| 32 | 2970162411 |