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 | 4 |
| 3 | 14 |
| 4 | 56 |
| 5 | 237 |
| 6 | 1046 |
| 7 | 4762 |
| 8 | 22198 |
| 9 | 105430 |
| 10 | 508384 |
| 11 | 2482297 |
| 12 | 12248416 |
| 13 | 60980875 |
| 14 | 305955356 |
| 15 | 1545397464 |
| 16 | 7852100294 |
| 17 | 40105277640 |
| 18 | 205798130604 |
| 19 | 1060467961508 |
| 20 | 5485199090812 |
| 21 | 28469067353686 |
| 22 | 148220323891460 |