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) |
|---|---|
| 3 | 1 |
| 4 | 4 |
| 5 | 17 |
| 6 | 82 |
| 7 | 422 |
| 8 | 2274 |
| 9 | 12665 |
| 10 | 72326 |
| 11 | 421214 |
| 12 | 2492112 |
| 13 | 14937210 |
| 14 | 90508256 |
| 15 | 553492552 |
| 16 | 3411758334 |
| 17 | 21175624713 |
| 18 | 132226234854 |
| 19 | 830077057878 |
| 20 | 5235817447752 |
| 21 | 33166634502334 |
| 22 | 210904780742860 |
| 23 | 1345806528336772 |
| 24 | 8614979593487972 |
| 25 | 55307373497626442 |
| 26 | 356012579697723084 |