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 | -5 |
| 3 | -17 |
| 4 | 1 |
| 5 | 121 |
| 6 | 235 |
| 7 | -377 |
| 8 | -2399 |
| 9 | -2159 |
| 10 | 12475 |
| 11 | 40063 |
| 12 | -7199 |
| 13 | -294839 |
| 14 | -539285 |
| 15 | 985303 |
| 16 | 5745601 |
| 17 | 4594081 |
| 18 | -31031045 |
| 19 | -94220657 |
| 20 | 28776001 |
| 21 | 717096601 |
| 22 | 1232761195 |
| 23 | -2554153817 |
| 24 | -13737635999 |
| 25 | -9596195279 |
| 26 | 76971061435 |
| 27 | 221115489823 |
| 28 | -96566450399 |
| 29 | -1740941329559 |