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%I #12 Jun 20 2022 21:33:19
%S 1336,1690,2324,3616,6076,11140,21164,42076,84556,174700,361484,
%T 766156,1619596,3513100,7574924,16818316,36974476,84005260,188124044,
%U 436672396,994194316,2351102860,5427635084,13031887756,30417011596,73894388620
%N Number of (n+1) X (6+1) 0..2 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 2 (constant-stress 1 X 1 tilings).
%H R. H. Hardin, <a href="/A234264/b234264.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) + 6*a(n-2) - 24*a(n-3) + 4*a(n-4) + 36*a(n-5) - 24*a(n-6).
%F Empirical g.f.: 2*x*(668 - 1159*x - 5381*x^2 + 9284*x^3 + 8250*x^4 - 13932*x^5) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)*(1 - 6*x^2)). - _Colin Barker_, Oct 14 2018
%e Some solutions for n=5:
%e 2 0 0 0 2 2 2 0 0 0 2 0 0 0 1 1 1 1 2 0 1
%e 2 2 0 2 2 0 2 0 2 0 0 0 2 0 0 2 0 2 1 1 0
%e 2 0 0 0 2 2 2 2 2 2 0 2 2 2 1 1 1 1 2 0 1
%e 2 2 0 2 2 0 2 0 2 0 0 0 2 0 0 2 0 2 1 1 0
%e 2 0 0 0 2 2 2 2 2 2 0 2 2 2 1 1 1 1 2 0 1
%e 0 0 2 0 0 2 0 0 2 0 0 0 2 0 0 2 0 2 1 1 0
%Y Column 6 of A234266.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 22 2013
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