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 | 14 |
| 3 | 84 |
| 4 | 556 |
| 5 | 3736 |
| 6 | 25612 |
| 7 | 177688 |
| 8 | 1244398 |
| 9 | 8777612 |
| 10 | 62271384 |
| 11 | 443847648 |
| 12 | 3175924636 |
| 13 | 22799963576 |
| 14 | 164142004184 |
| 15 | 1184574592592 |
| 16 | 8567000931404 |
| 17 | 62073936511496 |
| 18 | 450518481039956 |
| 19 | 3274628801768744 |
| 20 | 23833760489660324 |