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 | 20 |
| 4 | 110 |
| 5 | 638 |
| 6 | 3832 |
| 7 | 23592 |
| 8 | 147941 |
| 9 | 940982 |
| 10 | 6053180 |
| 11 | 39299408 |
| 12 | 257105146 |
| 13 | 1692931066 |
| 14 | 11208974860 |
| 15 | 74570549714 |
| 16 | 498174818986 |
| 17 | 3340366308393 |