Number of lower triangles of an n X n 0..3 array with each element differing from all of its horizontal and vertical neighbors by one.

A194993

Number of lower triangles of an n X n 0..3 array with each element differing from all of its horizontal and vertical neighbors by one.

Terms

    a(0) =4a(1) =10a(2) =42a(3) =248a(4) =2290a(5) =31042a(6) =641376a(7) =19753266a(8) =918924546a(9) =64065187024

External references