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A186211 Number of (n+1)X2 0..2 arrays with every 2X2 subblock determinant equal to some horizontal or vertical neighbor 2X2 subblock determinant.

%I A186211 #8 Jul 22 2025 10:19:22
%S A186211 0,175,609,3593,15055,76263,353985,1729733,8225815,39664199,189800057,
%T A186211 911926009,4372168391,20986330867,100672272185,483086490365,
%U A186211 2317736112319,11120991460315,53358239027713,256018285828501
%N A186211 Number of (n+1)X2 0..2 arrays with every 2X2 subblock determinant equal to some horizontal or vertical neighbor 2X2 subblock determinant.
%C A186211 Column 1 of A186218
%H A186211 R. H. Hardin, <a href="/A186211/b186211.txt">Table of n, a(n) for n = 1..200</a>
%F A186211 Empirical: a(n)=6*a(n-1)+a(n-2)-48*a(n-3)+77*a(n-4)+28*a(n-5)-238*a(n-6)+230*a(n-7)-67*a(n-8)+170*a(n-9)+100*a(n-10)-432*a(n-11)+256*a(n-12)-532*a(n-13)+296*a(n-14)+144*a(n-15)-320*a(n-16)+512*a(n-17) for n>18
%e A186211 Some solutions for 3X2
%e A186211 ..1..0....1..0....0..2....0..2....1..1....2..0....2..1....0..0....0..2....0..0
%e A186211 ..1..0....1..1....0..0....0..0....1..1....2..0....1..1....1..0....0..1....0..0
%e A186211 ..0..0....1..2....0..0....1..1....1..1....1..0....1..2....2..0....0..1....0..2
%K A186211 nonn
%O A186211 1,2
%A A186211 _R. H. Hardin_ Feb 15 2011