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 | 3 |
| 3 | 10 |
| 4 | 35 |
| 5 | 123 |
| 6 | 427 |
| 7 | 1460 |
| 8 | 4923 |
| 9 | 16405 |
| 10 | 54131 |
| 11 | 177150 |
| 12 | 575731 |
| 13 | 1860047 |
| 14 | 5978715 |
| 15 | 19131880 |
| 16 | 60982859 |
| 17 | 193710249 |
| 18 | 613415779 |
| 19 | 1937102450 |
| 20 | 6101872707 |
| 21 | 19177314211 |
| 22 | 60147030923 |
| 23 | 188286357660 |
| 24 | 588394867675 |
| 25 | 1835791987133 |
| 26 | 5719198113747 |
| 27 | 17793060798310 |
| 28 | 55285581766163 |