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 | 36 |
| 6 | 101 |
| 7 | 280 |
| 8 | 788 |
| 9 | 2212 |
| 10 | 6186 |
| 11 | 17384 |
| 12 | 48755 |
| 13 | 136649 |
| 14 | 383584 |
| 15 | 1075734 |
| 16 | 3016924 |
| 17 | 8464693 |
| 18 | 23740844 |
| 19 | 66592246 |
| 20 | 186807727 |
| 21 | 523973400 |
| 22 | 1469769653 |
| 23 | 4122833303 |
| 24 | 11564436141 |
| 25 | 32438795011 |
| 26 | 90992182917 |
| 27 | 255234015580 |
| 28 | 715941436278 |
| 29 | 2008237780651 |