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 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 10 |
| 6 | 24 |
| 7 | 68 |
| 8 | 188 |
| 9 | 586 |
| 10 | 1722 |
| 11 | 5492 |
| 12 | 16924 |
| 13 | 55582 |
| 14 | 177278 |
| 15 | 594460 |
| 16 | 1944980 |
| 17 | 6628384 |
| 18 | 22132112 |
| 19 | 76421498 |
| 20 | 259359036 |
| 21 | 905416294 |
| 22 | 3114033930 |
| 23 | 10971347070 |
| 24 | 38157201530 |