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 | 0 |
| 2 | 1 |
| 3 | 1198 |
| 4 | 5609649 |
| 5 | 66218360625 |
| 6 | 1681287695542855 |
| 7 | 81644850343968535401 |
| 8 | 6945222145021508480249929 |
| 9 | 967335448974819561548523580438 |
| 10 | 209141786137614009701487336108267723 |