Number of n X n 0..3 arrays with values 0..3 introduced in row major order and no element equal to any horizontal or vertical neighbor.

A198709

Number of n X n 0..3 arrays with values 0..3 introduced in row major order and no element equal to any horizontal or vertical neighbor.

Terms

    a(0) =1a(1) =4a(2) =401a(3) =250031a(4) =851787199

External references