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) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 30 |
| 4 | 231 |
| 5 | 2453 |
| 6 | 33393 |
| 7 | 556999 |
| 8 | 11039026 |
| 9 | 254128870 |
| 10 | 6677972615 |
| 11 | 197547561340 |
| 12 | 6504619941881 |
| 13 | 236165840696980 |
| 14 | 9380353293627619 |
| 15 | 404848232250564042 |
| 16 | 18875601922237847288 |
| 17 | 945875935431064488637 |