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 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 32 |
| 5 | 194 |
| 6 | 1473 |
| 7 | 13424 |
| 8 | 142722 |
| 9 | 1734155 |
| 10 | 23704880 |
| 11 | 360035434 |
| 12 | 6015135425 |
| 13 | 109631190368 |
| 14 | 2164636394634 |
| 15 | 46027826357795 |
| 16 | 1048622566013472 |
| 17 | 25482771281706578 |
| 18 | 657965393430769025 |
| 19 | 17988006311731338448 |