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 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 9 |
| 5 | 32 |
| 6 | 119 |
| 7 | 466 |
| 8 | 1881 |
| 9 | 7788 |
| 10 | 32868 |
| 11 | 140907 |
| 12 | 611871 |
| 13 | 2685732 |
| 14 | 11896906 |
| 15 | 53115412 |
| 16 | 238767737 |
| 17 | 1079780412 |
| 18 | 4909067468 |
| 19 | 22424085244 |
| 20 | 102865595140 |
| 21 | 473678981820 |
| 22 | 2188774576575 |
| 23 | 10145798119530 |
| 24 | 47165267330415 |
| 25 | 219839845852692 |
| 26 | 1027183096151244 |
| 27 | 4810235214490986 |