%I #7 Jun 18 2022 23:38:00
%S 136,188,248,380,544,908,1400,2492,4096,7628,13208,25340,45664,89228,
%T 165560,326972,619456,1230668,2366168,4715900,9162784,18292748,
%U 35811320,71557052,140857216,281583308,556527128,1112792060,2205927904,4411331468
%N Number of (n+1) X (4+1) 0..3 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant-stress 1 X 1 tilings).
%C Column 4 of A235289
%H R. H. Hardin, <a href="/A235285/b235285.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) +3*a(n-2) -15*a(n-3) +4*a(n-4) +18*a(n-5) -12*a(n-6).
%e Some solutions for n=4:
%e 1 0 1 0 1 0 1 0 1 0 3 0 2 0 2 1 2 0 3 0
%e 0 3 0 3 0 3 0 3 0 3 1 2 0 2 0 3 0 2 1 2
%e 2 1 2 1 2 2 3 2 3 2 3 0 2 0 2 1 2 0 3 0
%e 0 3 0 3 0 3 0 3 0 3 2 3 1 3 1 3 0 2 1 2
%e 2 1 2 1 2 0 1 0 1 0 3 0 2 0 2 1 2 0 3 0
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 05 2014
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