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) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 22 |
| 5 | 93 |
| 6 | 389 |
| 7 | 1570 |
| 8 | 6144 |
| 9 | 23629 |
| 10 | 89551 |
| 11 | 335430 |
| 12 | 1244762 |
| 13 | 4583293 |
| 14 | 16765087 |
| 15 | 60980096 |
| 16 | 220724896 |
| 17 | 795540601 |
| 18 | 2856541663 |
| 19 | 10222762962 |
| 20 | 36475315442 |
| 21 | 129796579409 |
| 22 | 460757642587 |
| 23 | 1632012075912 |
| 24 | 5768986242408 |