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A183306 Half the number of nX5 binary arrays with no element equal to a strict majority of its horizontal and vertical neighbors.

%I A183306 #7 Jul 22 2025 08:47:57
%S A183306 3,9,42,178,910,4212,19899,94217,445859,2113257,10006598,47387904,
%T A183306 224418390,1062810762,5033385029,23837475807,112891241315,
%U A183306 534638647159,2531982065694,11991154349342,56788620500294,268943860673076
%N A183306 Half the number of nX5 binary arrays with no element equal to a strict majority of its horizontal and vertical neighbors.
%C A183306 Column 5 of A183312
%H A183306 R. H. Hardin, <a href="/A183306/b183306.txt">Table of n, a(n) for n = 1..200</a>
%F A183306 Empirical: a(n)=9*a(n-1)-26*a(n-2)+24*a(n-3)+47*a(n-4)-157*a(n-5)-43*a(n-6)+641*a(n-7)-643*a(n-8)-952*a(n-9)+3460*a(n-10)-2021*a(n-11)-2111*a(n-12)+2715*a(n-13)-1249*a(n-14)-4657*a(n-15)-1514*a(n-16)+1961*a(n-17)-1230*a(n-18)+6713*a(n-19)+8832*a(n-20)+10212*a(n-21)+1971*a(n-22)-6552*a(n-23)-2819*a(n-24)-2898*a(n-25)-973*a(n-26)+302*a(n-27)+433*a(n-28)+286*a(n-29) for n>31
%e A183306 Some solutions with a(1,1)=0 for 5X4
%e A183306 ..0..0..1..0....0..1..1..0....0..1..0..1....0..1..1..0....0..1..0..1
%e A183306 ..1..1..0..1....1..0..0..1....0..1..0..0....1..0..0..1....1..0..0..1
%e A183306 ..0..1..1..0....0..1..1..0....1..0..1..1....1..0..0..1....0..1..1..0
%e A183306 ..1..0..0..1....1..0..0..1....0..1..1..0....0..1..1..0....1..0..1..1
%e A183306 ..1..0..1..0....0..1..0..1....1..0..0..1....1..0..1..0....0..1..0..0
%K A183306 nonn
%O A183306 1,1
%A A183306 _R. H. Hardin_ Jan 03 2011