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 | 4 |
| 4 | 13 |
| 5 | 25 |
| 6 | 72 |
| 7 | 166 |
| 8 | 450 |
| 9 | 1124 |
| 10 | 2973 |
| 11 | 7603 |
| 12 | 19865 |
| 13 | 51199 |
| 14 | 132982 |
| 15 | 343290 |
| 16 | 888309 |
| 17 | 2292325 |
| 18 | 5918742 |
| 19 | 15258937 |
| 20 | 39329418 |