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) |
|---|---|
| 3 | 1 |
| 4 | 5 |
| 5 | 20 |
| 6 | 102 |
| 7 | 627 |
| 8 | 4461 |
| 9 | 36155 |
| 10 | 328849 |
| 11 | 3317272 |
| 12 | 36757822 |
| 13 | 443846693 |
| 14 | 5800991345 |
| 15 | 81593004021 |
| 16 | 1228906816941 |
| 17 | 19733699436636 |
| 18 | 336554404751966 |
| 19 | 6075478765948135 |
| 20 | 115734570482611885 |
| 21 | 2320148441078578447 |
| 22 | 48827637296350480457 |
| 23 | 1076313671861962141616 |