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 | 0 |
| 3 | -1 |
| 4 | -1 |
| 5 | -9 |
| 6 | -5 |
| 7 | -21 |
| 8 | -21 |
| 9 | -197 |
| 10 | -117 |
| 11 | -427 |
| 12 | -427 |
| 13 | -2501 |
| 14 | -1797 |
| 15 | -2909 |
| 16 | -2909 |
| 17 | -72877 |
| 18 | -65453 |