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 | 3 |
| 4 | 3 |
| 5 | 15 |
| 6 | 45 |
| 7 | 63 |
| 8 | 63 |
| 9 | 405 |
| 10 | 14175 |
| 11 | 51975 |
| 12 | 93555 |
| 13 | 15795 |
| 14 | 42567525 |
| 15 | 49116375 |
| 16 | 91216125 |
| 17 | 2170943775 |
| 18 | 19538493975 |
| 19 | 109185701625 |
| 20 | 3093594879375 |
| 21 | 10257709336875 |
| 22 | 428772250281375 |
| 23 | 281764621613475 |
| 24 | 158210081654625 |
| 25 | 160789593855515625 |