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 | 29 |
| 3 | -139 |
| 4 | 31737 |
| 5 | -1824151 |
| 6 | 313750293 |
| 7 | -51584719523 |
| 8 | 13137192234225 |
| 9 | -3947317975733039 |
| 10 | 1522475446731094285 |
| 11 | -702509124781480897211 |
| 12 | 389722900767594460770025 |
| 13 | -253710144786166583863030983 |
| 14 | 192285396891961478711402819077 |
| 15 | -167564604997707653568802119363795 |