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 | 6 |
| 2 | 54 |
| 3 | 636 |
| 4 | 9204 |
| 5 | 157584 |
| 6 | 3111312 |
| 7 | 69533472 |
| 8 | 1734229344 |
| 9 | 47733263232 |
| 10 | 1436801816448 |
| 11 | 46942939272960 |
| 12 | 1654215709835520 |
| 13 | 62533593070755840 |
| 14 | 2524077593084160000 |
| 15 | 108339176213529384960 |
| 16 | 4927173048408858531840 |
| 17 | 236673892535088351744000 |