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%I #9 Jun 19 2022 01:33:20
%S 154,670,2900,12578,54530,236496,1025770,4449942,19307284,83782730,
%T 363623322,1578383808,6852296402,29752369022,129201632884,
%U 561144450002,2437478108882,10589252938544,46009511768922,199934061184966
%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 4, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).
%H R. H. Hardin, <a href="/A235100/b235100.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) - 2*a(n-2) - 47*a(n-3) + 3*a(n-4) + 84*a(n-5) + 36*a(n-6).
%F Empirical g.f.: 2*x*(77 - 204*x - 741*x^2 + 428*x^3 + 1656*x^4 + 648*x^5) / ((1 - 3*x - 6*x^2)*(1 - 4*x - 4*x^2 + 11*x^3 + 6*x^4)). - _Colin Barker_, Oct 17 2018
%e Some solutions for n=5:
%e 0 1 0 3 3 1 2 4 6 1 5 2 3 2 0 6 0 2 6 4
%e 1 6 2 1 4 6 4 2 3 2 2 3 2 5 3 5 5 3 1 3
%e 4 5 3 6 6 4 6 0 0 3 0 5 4 3 0 6 3 5 6 4
%e 5 2 1 0 1 3 3 1 5 4 2 3 6 1 2 4 0 6 4 6
%e 4 5 0 3 4 2 4 6 6 1 0 5 3 2 4 2 1 3 2 0
%e 1 6 5 4 1 3 3 1 3 2 1 2 1 4 3 5 2 0 1 3
%Y Column 1 of A235107.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 03 2014