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 | 168 |
| 2 | 17024 |
| 3 | 1354752 |
| 4 | 93499392 |
| 5 | 5881430016 |
| 6 | 346987429888 |
| 7 | 19548208103424 |
| 8 | 1064285732077568 |
| 9 | 56464495286943744 |
| 10 | 2936605030892961792 |
| 11 | 150373246607730671616 |
| 12 | 7606369972746352328704 |
| 13 | 381025640076812853706752 |