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 | 56 |
| 3 | 166320 |
| 4 | 4084080 |
| 5 | 698377680 |
| 6 | 146659312800 |
| 7 | 1075501627200 |
| 8 | 37104806138400 |
| 9 | 296838449107200 |
| 10 | 86825246363856000 |
| 11 | 96472495959840000 |
| 12 | 35251050023725536000 |
| 13 | 272194921062320256000 |
| 14 | 408292381593480384000 |
| 15 | 4082923815934803840000 |
| 16 | 15106818118958774208000 |