Number of n X n symmetric 0..6 arrays with no element equal to the sum or difference mod 7 of any two of its horizontal and vertical neighbors.

A193785

Number of n X n symmetric 0..6 arrays with no element equal to the sum or difference mod 7 of any two of its horizontal and vertical neighbors.

Terms

    a(0) =7a(1) =120a(2) =2424a(3) =139320a(4) =19924728a(5) =7436532066

External references