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%I
%S 40,208,632,2344,6232,20440,51800,160888,401560,1215928,3032792,
%T 9077944,22776472,67860280
%N Number of (n+1) X (n+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 5 (constant-stress 1 X 1 tilings).
%C Diagonal of A235280.
%F Empirical: a(n) = a(n-1) +23*a(n-2) -23*a(n-3) -200*a(n-4) +200*a(n-5) +820*a(n-6) -820*a(n-7) -1584*a(n-8) +1584*a(n-9) +1152*a(n-10) -1152*a(n-11) [see A235280 for an assumption].
%e Some solutions for n=4:
%e 4 1 4 2 4 4 1 3 1 4 2 4 1 4 1 0 3 0 2 0
%e 0 2 0 3 0 1 3 0 3 1 4 1 3 1 3 3 1 3 0 3
%e 4 1 4 2 4 4 1 3 1 4 2 4 1 4 1 0 3 0 2 0
%e 1 3 1 4 1 1 3 0 3 1 3 0 2 0 2 4 2 4 1 4
%e 4 1 4 2 4 3 0 2 0 3 2 4 1 4 1 0 3 0 2 0
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 05 2014
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