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 | 17 |
| 4 | 50 |
| 5 | 146 |
| 6 | 430 |
| 7 | 1267 |
| 8 | 3746 |
| 9 | 11091 |
| 10 | 32900 |
| 11 | 97716 |
| 12 | 290586 |
| 13 | 864980 |
| 14 | 2577032 |
| 15 | 7683397 |
| 16 | 22922874 |
| 17 | 68427057 |
| 18 | 204362172 |
| 19 | 610604629 |
| 20 | 1825092080 |
| 21 | 5457016431 |
| 22 | 16321318264 |
| 23 | 48828168580 |
| 24 | 146112907266 |
| 25 | 437319580738 |
| 26 | 1309158060068 |