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 | 2 |
| 3 | 6 |
| 4 | 16 |
| 5 | 48 |
| 6 | 149 |
| 7 | 460 |
| 8 | 1471 |
| 9 | 4702 |
| 10 | 15126 |
| 11 | 48607 |
| 12 | 156417 |
| 13 | 502137 |
| 14 | 1608406 |
| 15 | 5130178 |
| 16 | 16278890 |
| 17 | 51297616 |
| 18 | 160220536 |
| 19 | 494647640 |
| 20 | 1504567216 |
| 21 | 4491151455 |
| 22 | 13098763174 |
| 23 | 37146270208 |
| 24 | 101880559018 |
| 25 | 268650665645 |