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 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | -1 |
| 10 | -1 |
| 11 | 41 |
| 12 | 41 |
| 13 | -589 |
| 14 | -589 |
| 15 | 8317 |
| 16 | 8317 |
| 17 | -869807 |
| 18 | -869807 |
| 19 | 43056421 |
| 20 | 43056421 |
| 21 | -250158593 |
| 22 | -250158593 |
| 23 | 67632514765 |
| 24 | 67632514765 |
| 25 | -1581439548217 |
| 26 | -1581439548217 |