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 | 4 |
| 3 | 19 |
| 4 | 103 |
| 5 | 422 |
| 6 | 1559 |
| 7 | 5645 |
| 8 | 19329 |
| 9 | 64040 |
| 10 | 207637 |
| 11 | 663845 |
| 12 | 2103055 |