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 | 5 |
| 5 | -7 |
| 6 | -49 |
| 7 | -53 |
| 8 | 2215 |
| 9 | 1259 |
| 10 | -14201 |
| 11 | -183197 |
| 12 | 248885 |
| 13 | 9583753 |
| 14 | 14525053 |
| 15 | -554173253 |
| 16 | -4573299625 |
| 17 | 99833187251 |
| 18 | 215440236599 |
| 19 | -1654012631597 |
| 20 | -84480933600305 |
| 21 | -36267273557287 |
| 22 | 10992430255511053 |
| 23 | 117548575473066241 |
| 24 | -1380910044674479865 |