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 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 18 |
| 6 | 56 |
| 7 | 165 |
| 8 | 563 |
| 9 | 1937 |
| 10 | 7086 |
| 11 | 26396 |
| 12 | 101383 |
| 13 | 395821 |
| 14 | 1573317 |
| 15 | 6335511 |
| 16 | 25825861 |
| 17 | 106344587 |
| 18 | 441919711 |
| 19 | 1851114466 |
| 20 | 7809848543 |
| 21 | 33162241547 |
| 22 | 141636863809 |
| 23 | 608144007472 |
| 24 | 2623832050460 |
| 25 | 11370768445682 |
| 26 | 49478287669666 |
| 27 | 216109924932762 |
| 28 | 947216963083175 |