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 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 6 |
| 6 | 13 |
| 7 | 33 |
| 8 | 84 |
| 9 | 208 |
| 10 | 522 |
| 11 | 1341 |
| 12 | 3476 |
| 13 | 9042 |
| 14 | 23673 |
| 15 | 62426 |
| 16 | 165504 |
| 17 | 440664 |
| 18 | 1178168 |
| 19 | 3162357 |
| 20 | 8517681 |
| 21 | 23013294 |
| 22 | 62356329 |
| 23 | 169408107 |
| 24 | 461366499 |
| 25 | 1259311824 |
| 26 | 3444497550 |
| 27 | 9439766700 |
| 28 | 25916832981 |
| 29 | 71274793968 |
| 30 | 196325540206 |
| 31 | 541579442133 |