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 | 2 |
| 3 | 6 |
| 4 | 24 |
| 5 | 80 |
| 6 | 326 |
| 7 | 1566 |
| 8 | 9544 |
| 9 | 53696 |
| 10 | 347382 |
| 11 | 2566892 |
| 12 | 21907934 |
| 13 | 184868860 |
| 14 | 1704360992 |
| 15 | 17294597926 |
| 16 | 192725663600 |
| 17 | 2139133978996 |