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 | 4 |
| 2 | 20 |
| 3 | 140 |
| 4 | 1460 |
| 5 | 23884 |
| 6 | 639156 |
| 7 | 28895052 |
| 8 | 2260707508 |
| 9 | 311748794188 |
| 10 | 76846781851828 |
| 11 | 34240231941576524 |
| 12 | 27825184844063467700 |
| 13 | 41547951604100714698572 |
| 14 | 114705005843089453002549428 |