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 | 7 |
| 3 | 23 |
| 4 | 59 |
| 5 | 135 |
| 6 | 291 |
| 7 | 607 |
| 8 | 1243 |
| 9 | 2519 |
| 10 | 5075 |
| 11 | 10191 |
| 12 | 20427 |
| 13 | 40903 |
| 14 | 81859 |
| 15 | 163775 |
| 16 | 327611 |
| 17 | 655287 |
| 18 | 1310643 |
| 19 | 2621359 |
| 20 | 5242795 |
| 21 | 10485671 |
| 22 | 20971427 |
| 23 | 41942943 |
| 24 | 83885979 |
| 25 | 167772055 |
| 26 | 335544211 |
| 27 | 671088527 |
| 28 | 1342177163 |
| 29 | 2684354439 |