Number of nX4 0..3 arrays with exactly floor(nX4/2) elements equal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

A222743

Number of nX4 0..3 arrays with exactly floor(nX4/2) elements equal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

Terms

    a(0) =6a(1) =657a(2) =126947a(3) =27397461a(4) =6178897165

External references