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 | 4 |
| 2 | 59 |
| 3 | 275 |
| 4 | 4924 |
| 5 | 58623 |
| 6 | 506877 |
| 7 | 4546755 |
| 8 | 30224014 |
| 9 | 87818618 |
| 10 | 2836649805 |
| 11 | 14748299309 |
| 12 | 251285857122 |
| 13 | 603200604933 |
| 14 | 17530836835060 |
| 15 | 80446298927642 |
| 16 | 2054098188682332 |
| 17 | 9577010472498628 |
| 18 | 67026825574168206 |
| 19 | 1605887402218872982 |
| 20 | 16520076587958693329 |
| 21 | 156502536697199220470 |