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A185791 Number of (n+1) X 3 binary arrays with no 2 X 2 subblock sum equal to any horizontal or vertical neighbor 2 X 2 subblock sum. 1

%I

%S 40,96,224,576,1408,3456,8320,20864,50816,125312,304768,756096,

%T 1844864,4548992,11110016,27429248,67069568,165194112,404309632,

%U 995805568,2438669952,6000273792,14703462016,36167944576,88660698752,217982249344

%N Number of (n+1) X 3 binary arrays with no 2 X 2 subblock sum equal to any horizontal or vertical neighbor 2 X 2 subblock sum.

%C Column 2 of A185798.

%H R. H. Hardin, <a href="/A185791/b185791.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = a(n-1) + 2*a(n-2) + 16*a(n-4) - 16*a(n-5).

%F Empirical g.f.: 8*x*(5 + 7*x + 6*x^2 + 20*x^3 - 32*x^4) / (1 - x - 2*x^2 - 16*x^4 + 16*x^5). - _Colin Barker_, Apr 16 2018

%e Some solutions for 5 X 3:

%e ..0..1..0....1..1..1....1..0..0....0..0..1....0..0..0....0..0..1....0..1..1

%e ..1..0..0....0..1..1....0..0..0....0..0..1....1..1..0....0..0..1....0..1..1

%e ..0..0..0....0..0..1....0..0..1....0..1..1....1..0..1....1..1..1....0..0..0

%e ..0..0..1....0..0..0....1..0..1....0..1..1....0..1..1....1..0..0....1..1..0

%e ..0..1..1....1..0..0....0..1..1....0..0..0....0..0..0....0..0..0....1..0..1

%Y Cf. A185798.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 04 2011

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Last modified January 27 19:57 EST 2023. Contains 359848 sequences. (Running on oeis4.)