A047676 Main diagonal of square array defined in A047675.
1, 4, 2304, 584325558976905216, 35313389841821364727572472840336561596134691007780285818034354666813122266941990584103364198400
Offset: 0
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.