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%I #6 Jun 20 2022 01:46:31
%S 90,1490,34608,1525462,128653892,24740904388,10857686727324,
%T 11461385380110162
%N Number of (n+1) X (n+1) 0..5 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 2, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).
%e Some solutions for n=3:
%e 3 4 0 1 0 3 2 3 1 2 1 0 3 5 0 1 0 1 4 5
%e 0 3 1 4 3 4 1 4 4 3 4 1 0 4 1 4 1 0 1 4
%e 3 4 0 1 2 5 4 5 3 4 3 2 3 5 4 5 4 5 4 5
%e 4 3 1 4 0 1 2 1 4 3 0 1 0 4 1 0 3 2 3 2
%Y Diagonal of A234991.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 02 2014