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 | 9 |
| 3 | 27 |
| 4 | 82 |
| 5 | 249 |
| 6 | 756 |
| 7 | 2295 |
| 8 | 6967 |
| 9 | 21150 |
| 10 | 64206 |
| 11 | 194913 |
| 12 | 591706 |
| 13 | 1796268 |
| 14 | 5453010 |
| 15 | 16553943 |
| 16 | 50253535 |
| 17 | 152556873 |
| 18 | 463123629 |
| 19 | 1405924830 |
| 20 | 4268028025 |
| 21 | 12956640948 |
| 22 | 39333046473 |
| 23 | 119405064249 |
| 24 | 362483220772 |
| 25 | 1100406303264 |