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 | 2 |
| 3 | 6 |
| 4 | 19 |
| 5 | 71 |
| 6 | 300 |
| 7 | 1370 |
| 8 | 6563 |
| 9 | 32272 |
| 10 | 161700 |
| 11 | 820166 |
| 12 | 4198764 |
| 13 | 21647353 |
| 14 | 112262033 |
| 15 | 585049063 |
| 16 | 3061951973 |
| 17 | 16084816384 |
| 18 | 84773694223 |