Number of nX4 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than one of its immediate leftward or upward neighbors.

A208171

Number of nX4 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than one of its immediate leftward or upward neighbors.

Terms

    a(0) =15a(1) =2277a(2) =473928a(3) =99752346a(4) =21002874867

External references