Number of nX4 0..6 arrays with values 0..6 introduced in row major order and each element equal to at least one horizontal or vertical neighbor.

A198651

Number of nX4 0..6 arrays with values 0..6 introduced in row major order and each element equal to at least one horizontal or vertical neighbor.

Terms

    a(0) =2a(1) =76a(2) =3904a(3) =344008a(4) =39898934a(5) =5870175231a(6) =996290832880

External references