Number of n X n arrays of squares of integers, symmetric about main diagonal, with all rows summing to 6.

A156440

Number of n X n arrays of squares of integers, symmetric about main diagonal, with all rows summing to 6.

Terms

    a(0) =4a(1) =42a(2) =552a(3) =13751a(4) =425674a(5) =18458342a(6) =1164072896a(7) =139921844820

External references