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 | 6 |
| 3 | -15 |
| 4 | 33 |
| 5 | -68 |
| 6 | 134 |
| 7 | -253 |
| 8 | 460 |
| 9 | -811 |
| 10 | 1394 |
| 11 | -2344 |
| 12 | 3863 |
| 13 | -6253 |
| 14 | 9964 |
| 15 | -15653 |
| 16 | 24269 |
| 17 | -37178 |
| 18 | 56331 |
| 19 | -84489 |
| 20 | 125529 |
| 21 | -184867 |
| 22 | 270027 |
| 23 | -391391 |
| 24 | 563205 |
| 25 | -804925 |
| 26 | 1142998 |
| 27 | -1613195 |
| 28 | 2263675 |
| 29 | -3159023 |
| 30 | 4385502 |
| 31 | -6057865 |
| 32 | 8328200 |
| 33 | -11397371 |
| 34 | 15529768 |