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 | 14 |
| 3 | 72 |
| 4 | 388 |
| 5 | 2150 |
| 6 | 12134 |
| 7 | 69370 |
| 8 | 400398 |
| 9 | 2328162 |
| 10 | 13616892 |
| 11 | 80022612 |
| 12 | 472133638 |
| 13 | 2794893246 |
| 14 | 16592160944 |
| 15 | 98743919468 |
| 16 | 588913687966 |
| 17 | 3518968100982 |
| 18 | 21062444053040 |
| 19 | 126256612255260 |
| 20 | 757853797478188 |