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%I #12 Jun 20 2022 21:33:37
%S 244,358,560,988,1816,3616,7304,15544,33064,73288,161000,367528,
%T 826216,1930216,4416104,10507624,24366184,58801768,137742440,
%U 335934568,792768616,1948301416,4622131304,11420979304,27195392104,67451347048
%N Number of (n+1) X (4+1) 0..2 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 2 (constant-stress 1 X 1 tilings).
%H R. H. Hardin, <a href="/A234262/b234262.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) + 6*a(n-2) - 24*a(n-3) + 4*a(n-4) + 36*a(n-5) - 24*a(n-6).
%F Empirical g.f.: 2*x*(122 - 187*x - 989*x^2 + 1508*x^3 + 1554*x^4 - 2268*x^5) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)*(1 - 6*x^2)). - _Colin Barker_, Oct 14 2018
%e Some solutions for n=5:
%e 2 2 0 0 0 0 0 0 0 0 0 2 0 2 0 2 2 1 0 0
%e 2 0 0 2 0 2 0 2 0 2 0 0 0 0 0 2 0 1 2 0
%e 2 2 0 0 0 0 0 0 0 0 0 2 0 2 0 2 2 1 0 0
%e 2 0 0 2 0 2 0 2 0 2 1 1 1 1 1 2 0 1 2 0
%e 2 2 0 0 0 2 2 2 2 2 2 0 2 0 2 2 2 1 0 0
%e 2 0 0 2 0 2 0 2 0 2 2 2 2 2 2 2 0 1 2 0
%Y Column 4 of A234266.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 22 2013
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