1/120 the number of (n+1)X(n+1) 0..4 arrays with every 2X2 subblock containing four distinct values.

A183614

1/120 the number of (n+1)X(n+1) 0..4 arrays with every 2X2 subblock containing four distinct values.

Terms

    a(0) =1a(1) =56a(2) =7792a(3) =2708848a(4) =2359936032

External references