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) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 5 |
| 7 | 10 |
| 8 | 24 |
| 9 | 63 |
| 10 | 165 |
| 11 | 467 |
| 12 | 1405 |
| 13 | 4435 |
| 14 | 14775 |
| 15 | 51814 |
| 16 | 190443 |
| 17 | 732472 |
| 18 | 2939612 |
| 19 | 12277230 |
| 20 | 53233295 |
| 21 | 239083372 |
| 22 | 1109921554 |
| 23 | 5316143531 |
| 24 | 26225625392 |
| 25 | 133050795412 |
| 26 | 693227353094 |
| 27 | 3704785464812 |
| 28 | 20285853687809 |
| 29 | 113690627637475 |
| 30 | 651559904414667 |