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 | 8 |
| 3 | 21 |
| 4 | 93 |
| 5 | 314 |
| 6 | 1213 |
| 7 | 4375 |
| 8 | 16334 |
| 9 | 59925 |
| 10 | 221799 |
| 11 | 817280 |
| 12 | 3018301 |
| 13 | 11134189 |
| 14 | 41096528 |
| 15 | 151643937 |
| 16 | 559640289 |
| 17 | 2065192514 |
| 18 | 7621289593 |
| 19 | 28124714395 |
| 20 | 103789150046 |
| 21 | 383013144129 |
| 22 | 1413437041011 |
| 23 | 5216013647648 |
| 24 | 19248692843977 |