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) |
|---|---|
| 3 | 1 |
| 4 | 3 |
| 5 | 5 |
| 6 | 31 |
| 7 | 120 |
| 8 | 491 |
| 9 | 2016 |
| 10 | 8039 |
| 11 | 31884 |
| 12 | 126281 |
| 13 | 498558 |
| 14 | 1965077 |
| 15 | 7740246 |
| 16 | 30473582 |
| 17 | 119948507 |
| 18 | 472129697 |
| 19 | 1858535320 |
| 20 | 7317392228 |
| 21 | 28816569762 |
| 22 | 113512547183 |
| 23 | 447270667394 |
| 24 | 1762899256258 |
| 25 | 6950527615283 |
| 26 | 27412071431285 |