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) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 24 |
| 4 | 67 |
| 5 | 195 |
| 6 | 580 |
| 7 | 1730 |
| 8 | 5179 |
| 9 | 15533 |
| 10 | 46578 |
| 11 | 139712 |
| 12 | 419115 |
| 13 | 1257319 |
| 14 | 3771930 |
| 15 | 11315764 |
| 16 | 33947261 |
| 17 | 101841751 |
| 18 | 305525228 |
| 19 | 916575642 |
| 20 | 2749726883 |