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 | 8 |
| 3 | 152 |
| 4 | 4544 |
| 5 | 202176 |
| 6 | 10964160 |
| 7 | 1200365568 |
| 8 | 150015836160 |
| 9 | 27805483008000 |