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 | 4 |
| 3 | 10 |
| 4 | 33 |
| 5 | 91 |
| 6 | 277 |
| 7 | 792 |
| 8 | 2341 |
| 9 | 6654 |
| 10 | 18802 |
| 11 | 51508 |
| 12 | 138147 |
| 13 | 359457 |
| 14 | 910756 |
| 15 | 2240915 |
| 16 | 5365106 |
| 17 | 12495406 |
| 18 | 28353714 |
| 19 | 62725603 |
| 20 | 135469991 |
| 21 | 285904968 |
| 22 | 590347527 |
| 23 | 1193817552 |
| 24 | 2366907846 |
| 25 | 4605225266 |
| 26 | 8801576140 |
| 27 | 16538061290 |