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%I #9 Jun 19 2022 01:25:29
%S 264,488,936,1912,4008,8760,19560,44952,105128,250744,605928,1483288,
%T 3663912,9124728,22858344,57552408,145440680,368673400,936669672,
%U 2384161816,6076987176,15506905464,39603020136,101209873944,258785240744
%N Number of (n+1) X (3+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 3, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).
%H R. H. Hardin, <a href="/A235012/b235012.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) + 4*a(n-2) - 30*a(n-3) + 7*a(n-4) + 74*a(n-5) - 46*a(n-6) - 60*a(n-7) + 48*a(n-8).
%F Empirical g.f.: 8*x*(33 - 71*x - 259*x^2 + 517*x^3 + 676*x^4 - 1224*x^5 - 584*x^6 + 944*x^7) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)*(1 - 3*x^2)*(1 - x - 4*x^2)). - _Colin Barker_, Oct 16 2018
%e Some solutions for n=4:
%e 4 2 0 1 3 2 1 2 0 1 0 2 2 3 4 3 0 4 0 4
%e 0 1 2 0 2 4 0 4 4 2 4 3 0 4 2 4 1 2 1 2
%e 4 2 0 1 4 3 2 3 0 1 0 2 1 2 3 2 2 0 2 0
%e 0 1 2 0 2 4 0 4 4 2 4 3 2 0 4 0 1 2 1 2
%e 4 2 0 1 3 2 1 2 2 3 2 4 0 1 2 1 2 0 2 0
%Y Column 3 of A235017.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 02 2014
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