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 | 3 |
| 3 | 1 |
| 4 | 11 |
| 5 | 6 |
| 6 | 42 |
| 7 | 21 |
| 8 | 171 |
| 9 | 85 |
| 10 | 683 |
| 11 | 342 |
| 12 | 2730 |
| 13 | 1365 |
| 14 | 10923 |
| 15 | 5461 |
| 16 | 43691 |
| 17 | 21846 |
| 18 | 174762 |
| 19 | 87381 |
| 20 | 699051 |
| 21 | 349525 |
| 22 | 2796203 |
| 23 | 1398102 |
| 24 | 11184810 |
| 25 | 5592405 |
| 26 | 44739243 |
| 27 | 22369621 |
| 28 | 178956971 |
| 29 | 89478486 |
| 30 | 715827882 |
| 31 | 357913941 |
| 32 | 2863311531 |
| 33 | 1431655765 |