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 | 4 |
| 2 | 120 |
| 3 | 1230 |
| 4 | 7424 |
| 5 | 32424 |
| 6 | 113584 |
| 7 | 338742 |
| 8 | 893220 |
| 9 | 2136618 |
| 10 | 4721728 |
| 11 | 9770904 |