%I #4 Dec 18 2015 18:17:25

%S 1,2,12,1396,5147608,14289569180818

%N Number of n X n 1..n arrays with row and column sums n(n+1)/2 and no two adjacent elements equal.

%K nonn

%O 1,2

%A _R. H. Hardin_, Apr 16 2010