%I #13 Jun 20 2022 21:32:33
%S 160,1120,8064,58720,428800,3137920,22953984,168075520,1229731840,
%T 9005086720,65887739904,482487224320,3530236641280,25851483627520,
%U 189148815949824,1385113412485120,10134527552389120,74213894381240320
%N Number of (n+1) X (1+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 1 (constant-stress 1 X 1 tilings).
%H R. H. Hardin, <a href="/A234444/b234444.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 60*a(n-2) - 344*a(n-4).
%F Empirical g.f.: 32*x*(5 + 35*x - 48*x^2 - 265*x^3) / (1 - 60*x^2 + 344*x^4). - _Colin Barker_, Oct 15 2018
%e Some solutions for n=4:
%e 4 3 2 4 4 2 1 3 0 0 1 0 4 4 0 0 0 0 3 3
%e 2 2 2 3 2 1 3 4 0 1 4 4 3 2 0 1 4 3 3 2
%e 4 3 4 4 3 1 0 0 0 2 3 2 4 4 0 2 2 2 3 1
%e 2 2 1 2 2 1 1 2 2 3 4 2 1 0 3 4 1 2 4 1
%e 1 2 0 2 4 2 3 3 4 4 1 0 0 0 0 0 1 1 4 0
%Y Column 1 of A234450.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 26 2013
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