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 | -1 |
| 2 | 4 |
| 3 | -6 |
| 4 | 14 |
| 5 | -24 |
| 6 | 47 |
| 7 | -83 |
| 8 | 152 |
| 9 | -268 |
| 10 | 476 |
| 11 | -832 |
| 12 | 1453 |
| 13 | -2517 |
| 14 | 4348 |
| 15 | -7474 |
| 16 | 12810 |
| 17 | -21880 |
| 18 | 37275 |
| 19 | -63335 |
| 20 | 107376 |
| 21 | -181656 |
| 22 | 306744 |
| 23 | -517056 |
| 24 | 870169 |
| 25 | -1462249 |
| 26 | 2453812 |
| 27 | -4112478 |
| 28 | 6884102 |
| 29 | -11510808 |
| 30 | 19226951 |
| 31 | -32084027 |
| 32 | 53489288 |
| 33 | -89097892 |
| 34 | 148290068 |