Number of nX4 0..4 arrays with values 0..4 introduced in row major order and each element equal to one or two horizontal and vertical neighbors.

A198665

Number of nX4 0..4 arrays with values 0..4 introduced in row major order and each element equal to one or two horizontal and vertical neighbors.

Terms

    a(0) =2a(1) =65a(2) =2715a(3) =199923a(4) =16089057a(5) =1382332582a(6) =119026441960

External references