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 | 2 |
| 2 | 9 |
| 3 | 49 |
| 4 | 272 |
| 5 | 1509 |
| 6 | 8375 |
| 7 | 46586 |
| 8 | 259927 |
| 9 | 1454873 |
| 10 | 8167578 |
| 11 | 45975525 |
| 12 | 259412481 |
| 13 | 1466771294 |
| 14 | 8308711329 |
| 15 | 47142516717 |
| 16 | 267868554552 |
| 17 | 1524033271457 |
| 18 | 8681096155047 |
| 19 | 49500982033342 |
| 20 | 282533898125471 |
| 21 | 1614019099745197 |