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 | 9 |
| 3 | 37 |
| 4 | 186 |
| 5 | 985 |
| 6 | 5953 |
| 7 | 38689 |
| 8 | 271492 |
| 9 | 2016845 |
| 10 | 15767277 |
| 11 | 128792803 |
| 12 | 1094819196 |
| 13 | 9652396448 |
| 14 | 88040449618 |
| 15 | 829019941267 |
| 16 | 8044691126159 |
| 17 | 80322444793338 |
| 18 | 824036583310711 |
| 19 | 8675576699596604 |
| 20 | 93627696274152013 |