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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 3 |
| 6 | 10 |
| 7 | 25 |
| 8 | 63 |
| 9 | 144 |
| 10 | 327 |
| 11 | 711 |
| 12 | 1534 |
| 13 | 3237 |
| 14 | 6787 |
| 15 | 14056 |
| 16 | 28971 |
| 17 | 59283 |
| 18 | 120894 |
| 19 | 245457 |
| 20 | 497167 |
| 21 | 1004256 |
| 22 | 2025199 |
| 23 | 4077007 |
| 24 | 8198334 |
| 25 | 16467597 |
| 26 | 33052491 |
| 27 | 66293208 |