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 | 4 |
| 2 | 6 |
| 3 | 9 |
| 4 | 14 |
| 5 | 22 |
| 6 | 57 |
| 7 | 111 |
| 8 | 218 |
| 9 | 445 |
| 10 | 879 |
| 11 | 1754 |
| 12 | 3518 |
| 13 | 7034 |
| 14 | 14069 |
| 15 | 28129 |
| 16 | 56271 |
| 17 | 112529 |
| 18 | 225073 |
| 19 | 450139 |
| 20 | 900274 |
| 21 | 1800559 |
| 22 | 3601109 |
| 23 | 7202221 |
| 24 | 14404439 |
| 25 | 28808881 |
| 26 | 57617759 |
| 27 | 115235531 |
| 28 | 230471069 |
| 29 | 460942121 |