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%I #13 Jun 20 2022 21:33:00
%S 80,432,2368,13056,71936,397056,2188288,12079104,66572288,367472640,
%T 2025275392,11179327488,61613342720,340099792896,1874413748224,
%U 10346585653248,57023799492608,314765950844928,1734789723848704
%N Number of (n+1) X (1+1) 0..3 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 1 (constant-stress 1 X 1 tilings).
%H R. H. Hardin, <a href="/A234326/b234326.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 32*a(n-2) - 48*a(n-4).
%F Empirical g.f.: 16*x*(5 + 27*x - 12*x^2 - 48*x^3) / (1 - 32*x^2 + 48*x^4). - _Colin Barker_, Oct 14 2018
%e Some solutions for n=5:
%e 1 3 3 3 0 1 3 3 1 1 3 2 1 3 1 1 0 1 0 1
%e 2 3 0 1 1 1 1 0 2 1 0 0 0 3 1 2 2 2 0 0
%e 0 0 0 0 1 2 2 2 2 2 3 2 1 3 3 3 2 1 1 0
%e 0 1 2 1 0 0 1 0 1 2 2 2 1 2 1 2 0 0 3 3
%e 0 2 1 1 0 1 2 0 1 3 3 2 0 0 0 0 2 3 2 3
%e 0 3 1 2 2 2 1 0 1 2 0 0 1 0 3 2 2 2 0 2
%Y Column 1 of A234333.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 23 2013