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 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 12 |
| 6 | 35 |
| 7 | 133 |
| 8 | 497 |
| 9 | 2256 |
| 10 | 10123 |
| 11 | 53131 |
| 12 | 276210 |
| 13 | 1638039 |
| 14 | 9639943 |
| 15 | 63526677 |
| 16 | 416194299 |
| 17 | 3009639922 |
| 18 | 21672348693 |
| 19 | 170290649517 |
| 20 | 1334332599748 |
| 21 | 11302630861664 |
| 22 | 95587196023618 |
| 23 | 867197921850406 |
| 24 | 7862652321850812 |
| 25 | 75983785567389333 |
| 26 | 734442008292947615 |