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 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 0 |
| 5 | 2 |
| 6 | 20 |
| 7 | 0 |
| 8 | 272 |
| 9 | 1208 |
| 10 | 0 |
| 11 | 127334 |
| 12 | 1958084 |
| 13 | 0 |