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 | 2 |
| 2 | 6 |
| 3 | 19 |
| 4 | 60 |
| 5 | 188 |
| 6 | 589 |
| 7 | 1846 |
| 8 | 5786 |
| 9 | 18135 |
| 10 | 56840 |
| 11 | 178152 |
| 12 | 558377 |
| 13 | 1750106 |
| 14 | 5485310 |
| 15 | 17192459 |
| 16 | 53885860 |
| 17 | 168892996 |
| 18 | 529356757 |
| 19 | 1659148590 |
| 20 | 5200224626 |
| 21 | 16298923631 |
| 22 | 51085276240 |
| 23 | 160115201936 |
| 24 | 501844754065 |
| 25 | 1572918462066 |
| 26 | 4929955864374 |
| 27 | 15451827549123 |