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 | 4 |
| 3 | 15 |
| 4 | 60 |
| 5 | 245 |
| 6 | 1001 |
| 7 | 4085 |
| 8 | 16665 |
| 9 | 67985 |
| 10 | 277350 |
| 11 | 1131476 |
| 12 | 4615966 |
| 13 | 18831276 |
| 14 | 76823991 |
| 15 | 313410816 |
| 16 | 1278589392 |
| 17 | 5216127688 |
| 18 | 21279691689 |
| 19 | 86812537085 |
| 20 | 354160046356 |
| 21 | 1444829775128 |
| 22 | 5894321227301 |
| 23 | 24046447082350 |
| 24 | 98099780277675 |
| 25 | 400207434286276 |
| 26 | 1632684497403029 |