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 | 5 |
| 4 | 13 |
| 5 | 37 |
| 6 | 107 |
| 7 | 336 |
| 8 | 1037 |
| 9 | 3367 |
| 10 | 10924 |
| 11 | 36438 |
| 12 | 121045 |
| 13 | 412789 |
| 14 | 1398168 |
| 15 | 4831708 |
| 16 | 16636297 |
| 17 | 58084208 |
| 18 | 202101971 |
| 19 | 712709423 |
| 20 | 2502000811 |
| 21 | 8880033929 |
| 22 | 31428410158 |
| 23 | 112199775788 |
| 24 | 399383181020 |
| 25 | 1433385148187 |
| 26 | 5128572792587 |
| 27 | 18481258241133 |