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 | 7 |
| 3 | 20 |
| 4 | 61 |
| 5 | 174 |
| 6 | 514 |
| 7 | 1478 |
| 8 | 4303 |
| 9 | 12437 |
| 10 | 36084 |
| 11 | 104494 |
| 12 | 303167 |
| 13 | 879283 |
| 14 | 2552803 |
| 15 | 7413583 |
| 16 | 21544347 |
| 17 | 62635823 |
| 18 | 182199853 |
| 19 | 530228946 |
| 20 | 1543761513 |
| 21 | 4496523995 |
| 22 | 13102414665 |
| 23 | 38193626823 |
| 24 | 111375529695 |
| 25 | 324891970936 |
| 26 | 948051861938 |
| 27 | 2767336312386 |
| 28 | 8080206646244 |