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 | 9 |
| 3 | 21 |
| 4 | 122 |
| 5 | 228 |
| 6 | 1167 |
| 7 | 2123 |
| 8 | 11270 |
| 9 | 20440 |
| 10 | 110971 |
| 11 | 201475 |
| 12 | 1103592 |
| 13 | 2005388 |