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 | 15 |
| 2 | 575 |
| 3 | 46760 |
| 4 | 6998824 |
| 5 | 1744835904 |
| 6 | 673781602752 |
| 7 | 381495483224064 |
| 8 | 303443622431870976 |
| 9 | 327643295527342080000 |
| 10 | 466962174913357393920000 |
| 11 | 858175477913267353681920000 |
| 12 | 1993920215002599923346309120000 |
| 13 | 5758788816015998806424467537920000 |