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 | 4 |
| 4 | 16 |
| 5 | 56 |
| 6 | 256 |
| 7 | 1072 |
| 8 | 11264 |
| 9 | 78976 |
| 10 | 672256 |
| 11 | 4653056 |
| 12 | 49810432 |
| 13 | 433429504 |
| 14 | 4448608256 |
| 15 | 39221579776 |
| 16 | 607251736576 |
| 17 | 7244686764032 |
| 18 | 101611422797824 |
| 19 | 1170362064019456 |
| 20 | 19281174853615616 |
| 21 | 261583327556386816 |
| 22 | 4084459360167657472 |
| 23 | 54366023748591386624 |