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 | 5 |
| 3 | 26 |
| 4 | 189 |
| 5 | 1734 |
| 6 | 19305 |
| 7 | 253370 |
| 8 | 3828825 |
| 9 | 65473006 |
| 10 | 1249937325 |
| 11 | 26352843470 |
| 12 | 608142583125 |
| 13 | 15247003381854 |
| 14 | 412685556908625 |
| 15 | 11993673995924378 |
| 16 | 372509404162520625 |
| 17 | 12313505304343363126 |
| 18 | 431620764875678503125 |