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 | 3 |
| 3 | 8 |
| 4 | 25 |
| 5 | 73 |
| 6 | 234 |
| 7 | 717 |
| 8 | 2357 |
| 9 | 7480 |
| 10 | 25289 |
| 11 | 82837 |
| 12 | 289518 |
| 13 | 980017 |
| 14 | 3566993 |
| 15 | 12526980 |
| 16 | 47916421 |
| 17 | 175536777 |
| 18 | 712276698 |
| 19 | 2736099789 |
| 20 | 11863097885 |
| 21 | 47932689416 |
| 22 | 222692658177 |
| 23 | 946323358837 |
| 24 | 4700880455462 |
| 25 | 20946375415505 |
| 26 | 110626016074953 |
| 27 | 514550968010964 |