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 | 3 |
| 2 | 11 |
| 3 | 58 |
| 4 | 409 |
| 5 | 3606 |
| 6 | 38149 |
| 7 | 470856 |
| 8 | 6641793 |
| 9 | 105398650 |
| 10 | 1858413061 |
| 11 | 36044759796 |
| 12 | 762659322385 |
| 13 | 17481598316742 |
| 14 | 431535346662645 |
| 15 | 11413394655983536 |
| 16 | 321989729198400385 |
| 17 | 9651573930139850610 |
| 18 | 306321759739045148293 |
| 19 | 10262156907184058219340 |