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%I #10 Oct 21 2018 13:45:21
%S 16,32,60,120,252,496,972,1960,3980,7872,15676,31512,63260,125840,
%T 251692,504456,1009452,2014560,4031900,8069112,16136636,32249392,
%U 64530060,129075560,258121932,516130816,1032513532,2064979160,4129750620
%N Number of (n+1) X (1+1) 0..1 arrays colored with the sum of the upper and lower median values of each 2 X 2 subblock.
%H R. H. Hardin, <a href="/A236323/b236323.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-2) + 2*a(n-3) + 8*a(n-4).
%F Empirical g.f.: 4*x*(4 + 8*x + 11*x^2 + 14*x^3) / ((1 - 2*x)*(1 + 2*x + 3*x^2 + 4*x^3)). - _Colin Barker_, Oct 21 2018
%e Some solutions for n=5:
%e ..1..1....1..1....1..0....1..1....1..1....0..0....1..1....0..0....0..0....1..1
%e ..0..1....0..1....0..1....0..1....0..1....0..0....0..1....0..1....0..1....1..1
%e ..0..1....0..0....0..0....1..0....1..0....1..1....0..1....0..1....0..1....0..0
%e ..0..0....1..1....1..1....1..1....0..0....1..0....1..1....1..1....1..1....1..0
%e ..1..1....1..0....0..1....0..0....1..1....1..0....0..0....0..0....0..0....1..0
%e ..1..0....0..1....0..1....1..0....1..1....0..0....1..0....0..0....1..0....1..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 22 2014
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