Number of nX3 0..4 arrays with every nonzero element less than or equal to at least two horizontal and vertical neighbors.

A203341

Number of nX3 0..4 arrays with every nonzero element less than or equal to at least two horizontal and vertical neighbors.

Terms

    a(0) =1a(1) =25a(2) =635a(3) =9555a(4) =142167a(5) =2566719a(6) =48091042a(7) =870803077a(8) =15677729113a(9) =285592250536

External references