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 | 7 |
| 4 | 13 |
| 5 | 64 |
| 6 | 151 |
| 7 | 634 |
| 8 | 1693 |
| 9 | 6514 |
| 10 | 18688 |
| 11 | 68239 |
| 12 | 204631 |
| 13 | 722920 |
| 14 | 2230498 |
| 15 | 7711216 |
| 16 | 24246229 |
| 17 | 82612189 |
| 18 | 263112874 |
| 19 | 887565955 |
| 20 | 2852058448 |
| 21 | 9553983613 |
| 22 | 30892668295 |
| 23 | 102975387211 |
| 24 | 334454025715 |
| 25 | 1110899344549 |
| 26 | 3619669508056 |
| 27 | 11992016509234 |
| 28 | 39164977065622 |