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%I #7 Jan 18 2019 14:39:11
%S 4,11,27,76,185,489,1204,3059,7539,18748,46001,112977,275620,671387,
%T 1629003,3944428,9524969,22955577,55208404,132545027,317673891,
%U 760222300,1816668257,4335499425,10333941316,24603369515,58513434747,139020574348
%N Number of 2 X n binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.
%H R. H. Hardin, <a href="/A269076/b269076.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) + 5*a(n-2) - 6*a(n-3) - 9*a(n-4).
%F Empirical g.f.: x*(4 + 3*x - 15*x^2 - 9*x^3) / (1 - x - 3*x^2)^2. - _Colin Barker_, Jan 18 2019
%e Some solutions for n=4:
%e ..1..1..0..1. .0..0..1..0. .1..0..0..0. .1..0..0..0. .0..0..0..0
%e ..0..0..0..1. .0..0..0..1. .0..0..0..0. .0..0..1..1. .1..0..1..0
%Y Row 2 of A269075.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 19 2016
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