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%I #7 Jun 22 2022 11:19:43
%S 1321,1754,4023,9834,16083,34314,49407,109950,159879,350418,540777,
%T 1143302,1845649,3753244,6241282,12344866,21014030,40729476,70552158,
%U 134674572,236349786,446055356,790511890,1479273964,2640888394
%N Number of (n+1) X 7 0..2 arrays with every 2 X 2 subblock commuting with each of its horizontal and vertical 2 X 2 subblock neighbors.
%C Column 6 of A186472.
%H R. H. Hardin, <a href="/A186469/b186469.txt">Table of n, a(n) for n = 1..170</a>
%F Empirical: a(n) = 2*a(n-1)+a(n-2)-4*a(n-3)+4*a(n-4)-2*a(n-5) for n>15.
%e Some solutions for 3 X 7
%e ..2..0..0..0..2..0..1....2..2..0..0..0..0..1....2..1..0..0..0..1..0
%e ..2..0..0..0..0..2..0....1..0..2..0..0..0..1....1..0..1..0..0..0..1
%e ..2..0..0..0..0..0..2....0..1..0..2..0..0..1....0..1..0..1..0..0..2
%Y Cf. A186472.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 22 2011