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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 4 |
| 6 | 30 |
| 7 | 301 |
| 8 | 4985 |
| 9 | 142276 |
| 10 | 7269487 |
| 11 | 655015612 |
| 12 | 103031645470 |
| 13 | 28250197044039 |