Number of nX7 0..3 arrays with values 0..3 introduced in row major order, the number of instances of each value within one of each other, and every element equal to zero or two horizontal or vertical neighbors.

A199200

Number of nX7 0..3 arrays with values 0..3 introduced in row major order, the number of instances of each value within one of each other, and every element equal to zero or two horizontal or vertical neighbors.

Terms

    a(0) =41a(1) =14479a(2) =3366282a(3) =351517665a(4) =533423159945

External references