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 | 3 |
| 3 | 11 |
| 4 | 47 |
| 5 | 239 |
| 6 | 1237 |
| 7 | 6823 |
| 8 | 39323 |
| 9 | 239069 |
| 10 | 1525561 |
| 11 | 10225829 |
| 12 | 71726531 |
| 13 | 525861911 |
| 14 | 4020740833 |
| 15 | 32003840389 |
| 16 | 264714821617 |
| 17 | 2271484704413 |
| 18 | 20189330678347 |
| 19 | 185603551570757 |