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A184046 1/9 the number of (n+1) X 8 0..2 arrays with all 2 X 2 subblocks having the same four values.

%I A184046 #8 Apr 10 2018 14:34:47
%S A184046 289,295,305,325,361,433,569,841,1369,2425,4505,8665,16921,33433,
%T A184046 66329,132121,263449,526105,1050905,2100505,4198681,8395033,16785689,
%U A184046 33567001,67125529,134242585,268468505,536920345,1073807641,2147582233,4295098649
%N A184046 1/9 the number of (n+1) X 8 0..2 arrays with all 2 X 2 subblocks having the same four values.
%C A184046 Column 7 of A184048.
%H A184046 R. H. Hardin, <a href="/A184046/b184046.txt">Table of n, a(n) for n = 1..200</a>
%F A184046 Empirical: a(n) = 3*a(n-1) - 6*a(n-3) + 4*a(n-4).
%F A184046 Conjectures from _Colin Barker_, Apr 10 2018: (Start)
%F A184046 G.f.: x*(289 - 572*x - 580*x^2 + 1144*x^3) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)).
%F A184046 a(n) = 3*2^(n/2) + 2^(n+1) + 281 for n even.
%F A184046 a(n) = 2^(n+1) + 2^((n+3)/2) + 281 for n odd.
%F A184046 (End)
%e A184046 Some solutions for 5 X 8:
%e A184046 ..1..1..1..0..0..0..1..1....0..2..0..2..2..2..0..2....1..0..1..0..1..0..1..0
%e A184046 ..0..0..0..1..1..1..0..0....2..1..2..1..0..1..2..1....2..1..2..1..2..1..2..1
%e A184046 ..1..1..1..0..0..0..1..1....0..2..0..2..2..2..0..2....1..0..1..0..1..0..1..0
%e A184046 ..0..0..0..1..1..1..0..0....2..1..2..1..0..1..2..1....1..2..1..2..1..2..1..2
%e A184046 ..1..1..1..0..0..0..1..1....0..2..0..2..2..2..0..2....0..1..0..1..0..1..0..1
%Y A184046 Cf. A184048.
%K A184046 nonn
%O A184046 1,1
%A A184046 _R. H. Hardin_, Jan 08 2011