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 | 31 |
| 4 | 256 |
| 5 | 2960 |
| 6 | 44169 |
| 7 | 813298 |
| 8 | 17952898 |
| 9 | 465148507 |
| 10 | 13915349132 |
| 11 | 474372594032 |
| 12 | 18228772272441 |
| 13 | 782443669319410 |
| 14 | 37224994809379094 |
| 15 | 1949799331997896119 |
| 16 | 111783178753323665728 |
| 17 | 6978369826387194664144 |
| 18 | 472207139326449254997425 |