1/5 the number of n X 5 0..4 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors.

A185821

1/5 the number of n X 5 0..4 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors.

Terms

    a(0) =9a(1) =5680a(2) =1266624a(3) =378212944a(4) =100480040192

External references