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%I #8 Apr 16 2018 16:25:10
%S 16,40,100,260,676,1716,4356,11220,28900,73780,188356,483476,1240996,
%T 3174900,8122500,20822100,53377636,136666036,349914436,896578580,
%U 2297284900,5883599220,15068544516,38602941396,98893896676,253305662260
%N Number of (n+1) X 2 binary arrays with no 2 X 2 subblock sum equal to any horizontal or vertical neighbor 2 X 2 subblock sum.
%C Column 1 of A185798.
%H R. H. Hardin, <a href="/A185790/b185790.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = a(n-1) + 4*a(n-3) + 16*a(n-4).
%F Empirical g.f.: 4*x*(4 + 6*x + 15*x^2 + 24*x^3) / ((1 + 4*x^2)*(1 - x - 4*x^2)). - _Colin Barker_, Apr 16 2018
%e Some solutions for 3 X 2:
%e ..1..0....1..0....1..1....0..0....0..1....0..0....1..1....0..0....1..0....1..1
%e ..0..1....0..0....1..0....0..0....0..0....1..0....0..0....1..1....1..0....1..1
%e ..1..1....1..1....0..0....0..1....0..0....1..0....0..1....1..0....0..0....1..0
%Y Cf. A185798.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 04 2011
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