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 | 2 |
| 2 | 7 |
| 3 | 20 |
| 4 | 59 |
| 5 | 162 |
| 6 | 449 |
| 7 | 1200 |
| 8 | 3194 |
| 9 | 8348 |
| 10 | 21646 |
| 11 | 55480 |
| 12 | 141152 |
| 13 | 356056 |
| 14 | 892284 |
| 15 | 2221208 |
| 16 | 5497945 |
| 17 | 13533858 |
| 18 | 33151571 |
| 19 | 80826748 |
| 20 | 196219393 |
| 21 | 474425518 |
| 22 | 1142758067 |
| 23 | 2742784304 |
| 24 | 6561052331 |
| 25 | 15645062126 |
| 26 | 37194451937 |
| 27 | 88174252924 |
| 28 | 208463595471 |
| 29 | 491585775018 |