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 | 3 |
| 2 | 9 |
| 3 | 28 |
| 4 | 88 |
| 5 | 276 |
| 6 | 867 |
| 7 | 2724 |
| 8 | 8558 |
| 9 | 26886 |
| 10 | 84465 |
| 11 | 265355 |
| 12 | 833637 |
| 13 | 2618948 |
| 14 | 8227668 |
| 15 | 25847981 |
| 16 | 81203827 |
| 17 | 255109346 |
| 18 | 801449647 |
| 19 | 2517828323 |
| 20 | 7909990963 |
| 21 | 24849969499 |
| 22 | 78068481620 |
| 23 | 245259368334 |
| 24 | 770505029782 |
| 25 | 2420612941117 |