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 | 4 |
| 1 | 140 |
| 2 | 4056 |
| 3 | 129360 |
| 4 | 4381848 |
| 5 | 153700408 |
| 6 | 5519859080 |
| 7 | 201714989064 |