Number of n X n 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors.

A199141

Number of n X n 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors.

Terms

    a(0) =0a(1) =3a(2) =132a(3) =125468a(4) =839006010

External references