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%I #9 Jun 19 2022 01:17:36
%S 128,268,472,1116,2096,5316,10240,27060,52744,142876,280240,770572,
%T 1516768,4208188,8300136,23151620,45717872,127927396,252795808,
%U 708714660,1401057032,3932335452,7775722672,21838955052,43190207392,121354286332
%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 1, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).
%H R. H. Hardin, <a href="/A234877/b234877.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) + 11*a(n-2) - 23*a(n-3) - 38*a(n-4) + 87*a(n-5) + 46*a(n-6) - 130*a(n-7) - 16*a(n-8) + 78*a(n-9) - 16*a(n-11).
%F Empirical g.f.: 4*x*(32 + 3*x - 368*x^2 + 42*x^3 + 1425*x^4 - 312*x^5 - 2262*x^6 + 492*x^7 + 1496*x^8 - 192*x^9 - 344*x^10) / ((1 - x)*(1 - x - x^2)*(1 - 4*x^2 + 2*x^4)*(1 - 7*x^2 + 8*x^4)). - _Colin Barker_, Oct 16 2018
%e Some solutions for n=4:
%e 2 4 1 4 1 4 3 4 1 0 1 0 2 0 2 0 1 4 2 4
%e 1 2 0 2 0 2 0 2 4 2 4 2 4 1 4 1 0 2 1 2
%e 2 4 3 4 1 4 1 4 2 1 2 1 2 0 2 0 3 4 2 4
%e 0 3 1 3 0 2 0 2 4 2 4 2 4 1 4 3 1 3 0 1
%e 2 4 3 4 1 4 1 4 1 0 3 0 2 0 2 0 3 4 2 4
%Y Column 3 of A234882.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 01 2014
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