%I #9 Dec 01 2018 04:41:52

%S 5,10,18,34,68,136,268,528,1048,2088,4160,8288,16528,32992,65888,

%T 131616,262976,525568,1050560,2100224,4199040,8395904,16788480,

%U 33571840,67135744,134259200,268499456,536969728,1073894400,2147719168,4295330816

%N Number of length n+2 0..1 arrays with the sum of the maximum minus the median of adjacent triples multiplied by some arrangement of +-1 equal to zero.

%H R. H. Hardin, <a href="/A251928/b251928.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) - 6*a(n-2) + 6*a(n-3) - 4*a(n-4).

%F Empirical g.f.: x*(5 - 10*x + 8*x^2 - 8*x^3) / ((1 - 2*x)*(1 - 2*x + 2*x^2 - 2*x^3)). - _Colin Barker_, Dec 01 2018

%e Some solutions for n=6:

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

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

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

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

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

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

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

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

%Y Column 1 of A251935.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 11 2014