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 | 26 |
| 4 | 107 |
| 5 | 468 |
| 6 | 2141 |
| 7 | 10124 |
| 8 | 49101 |
| 9 | 242934 |
| 10 | 1221427 |
| 11 | 6222838 |
| 12 | 32056215 |
| 13 | 166690696 |
| 14 | 873798681 |
| 15 | 4612654808 |
| 16 | 24499322137 |
| 17 | 130830894666 |
| 18 | 702037771647 |
| 19 | 3783431872018 |
| 20 | 20469182526595 |
| 21 | 111133368084892 |
| 22 | 605312629105205 |
| 23 | 3306633429423460 |
| 24 | 18111655081108453 |