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%I #9 Jun 19 2022 21:22:24
%S 2554,4514,7810,14702,27218,53590,103702,210318,418838,866298,1758206,
%T 3687018,7583258,16071562,33396914,71419678,149733442,322890902,
%U 682659526,1484242286,3164667686,6938097082,14923990510,32998428714
%N Number of (n+1) X (6+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).
%H R. H. Hardin, <a href="/A235085/b235085.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) +4*a(n-2) -87*a(n-3) +90*a(n-4) +450*a(n-5) -830*a(n-6) -936*a(n-7) +2737*a(n-8) +408*a(n-9) -4078*a(n-10) +891*a(n-11) +2766*a(n-12) -816*a(n-13) -904*a(n-14) +180*a(n-15) +120*a(n-16).
%e Some solutions for n=5:
%e 0 2 1 3 1 2 0 1 0 2 1 2 1 2 3 4 2 3 2 4 1
%e 2 0 3 1 3 0 2 0 3 1 4 1 4 1 4 1 3 0 3 1 2
%e 0 2 1 3 1 2 0 1 0 2 1 2 1 2 3 4 2 3 2 4 1
%e 2 0 3 1 3 0 2 0 3 1 4 1 4 1 4 1 3 0 3 1 2
%e 0 2 1 3 1 2 0 3 2 4 3 4 3 4 2 3 1 2 1 3 0
%e 3 1 4 2 4 1 3 0 3 1 4 1 4 1 4 1 3 0 3 1 2
%Y Column 6 of A235087.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 03 2014