%I #7 Jun 18 2022 23:38:11
%S 836,968,1108,1400,1724,2408,3220,4952,7196,12008,18868,33560,56444,
%T 105128,186580,358232,660956,1292648,2448628,4839320,9327164,18539048,
%U 36139540,72049112,141513116,282566888,557838388,1114758680,2208549884
%N Number of (n+1) X (7+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 7 of A235289.
%H R. H. Hardin, <a href="/A235288/b235288.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 3 2 3 2 3 2 3 2 1 3 0 3 0 3 0 3 3 1 3 1 3 0 3 0
%e 0 3 0 3 0 3 0 3 3 1 2 1 2 1 2 1 1 3 1 3 1 2 1 2
%e 1 0 1 0 1 0 1 0 1 3 0 3 0 3 0 3 3 1 3 1 3 0 3 0
%e 0 3 0 3 0 3 0 3 2 0 1 0 1 0 1 0 1 3 1 3 1 2 1 2
%e 3 2 3 2 3 2 3 2 1 3 0 3 0 3 0 3 3 1 3 1 3 0 3 0
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 05 2014
|