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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 7 |
| 5 | 18 |
| 6 | 60 |
| 7 | 196 |
| 8 | 704 |
| 9 | 2500 |
| 10 | 9189 |
| 11 | 33896 |
| 12 | 126759 |
| 13 | 476270 |
| 14 | 1802312 |
| 15 | 6849777 |
| 16 | 26152418 |
| 17 | 100203194 |
| 18 | 385221143 |
| 19 | 1485200848 |
| 20 | 5741256764 |
| 21 | 22245940545 |
| 22 | 86383382827 |
| 23 | 336093325058 |
| 24 | 1309998125640 |
| 25 | 5114451441106 |
| 26 | 19998172734786 |
| 27 | 78306011677182 |
| 28 | 307022182222506 |
| 29 | 1205243866707468 |
| 30 | 4736694001644862 |