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%I #12 Jun 20 2022 21:30:20
%S 100,208,380,844,1660,3844,8012,19060,41500,100468,225740,552724,
%T 1269340,3130804,7297292,18083860,42569500,105816628,250733900,
%U 624493204,1486176220,3706326964,8845631372,22078365460,52792467100,131840507188
%N Number of (n+1) X (2+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 5 (constant-stress 1 X 1 tilings).
%H R. H. Hardin, <a href="/A235272/b235272.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 15*a(n-2) - 15*a(n-3) - 80*a(n-4) + 80*a(n-5) + 180*a(n-6) - 180*a(n-7) - 144*a(n-8) + 144*a(n-9).
%F Empirical g.f.: 4*x*(25 + 27*x - 332*x^2 - 289*x^3 + 1559*x^4 + 966*x^5 - 3078*x^6 - 1008*x^7 + 2160*x^8) / ((1 - x)*(1 - 2*x)*(1 + 2*x)*(1 - 2*x^2)*(1 - 3*x^2)*(1 - 6*x^2)). - _Colin Barker_, Oct 17 2018
%e Some solutions for n=4:
%e 2 4 2 0 3 0 4 1 3 1 3 2 3 1 3 1 3 0 0 4 0
%e 4 1 4 3 1 3 2 4 1 3 0 4 1 4 1 3 0 2 1 0 1
%e 2 4 2 1 4 1 3 0 2 1 3 2 4 2 4 2 4 1 0 4 0
%e 4 1 4 3 1 3 2 4 1 3 0 4 1 4 1 3 0 2 1 0 1
%e 1 3 1 0 3 0 4 1 3 2 4 3 3 1 3 2 4 1 0 4 0
%Y Column 2 of A235280.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 05 2014
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