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%I #12 Jun 20 2022 21:31:39
%S 360,2716,20416,153752,1157728,8726336,65777344,496308128,3744934912,
%T 28286490944,213660702976,1615562611712,12215896488448,92467959109376,
%U 699922909794304,5303754118235648,40188257800148992,304858331817979904
%N Number of (n+1) X (1+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 3 (constant-stress 1 X 1 tilings).
%H R. H. Hardin, <a href="/A234550/b234550.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 118*a(n-2) - 3660*a(n-4) + 10800*a(n-6).
%F Empirical g.f.: 4*x*(90 + 679*x - 5516*x^2 - 41684*x^3 + 16560*x^4 + 131040*x^5) / ((1 - 60*x^2)*(1 - 58*x^2 + 180*x^4)). - _Colin Barker_, Oct 15 2018
%e Some solutions for n=4:
%e 2 4 0 5 1 3 4 6 3 4 1 2 2 2 0 3 4 2 0 1
%e 1 0 2 4 5 4 2 1 2 0 1 5 3 0 0 0 4 5 3 1
%e 2 4 3 2 0 2 1 3 3 4 0 1 5 5 1 4 2 0 2 3
%e 5 4 0 2 3 2 1 0 2 0 3 1 6 3 5 5 2 3 4 2
%e 4 0 2 1 4 0 4 0 5 6 4 5 6 6 3 6 1 5 6 1
%Y Column 1 of A234555.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 28 2013
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