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 | 1 |
| 3 | 3 |
| 4 | 15 |
| 5 | 945 |
| 6 | 10395 |
| 7 | 2027025 |
| 8 | 34459425 |
| 9 | 13749310575 |
| 10 | 213458046676875 |
| 11 | 6190283353629375 |
| 12 | 221643095476699771875 |
| 13 | 319830986772877770815625 |
| 14 | 13113070457687988603440625 |
| 15 | 25373791335626257947657609375 |
| 16 | 2980227913743310874726229193921875 |