%I #4 Dec 27 2014 09:33:50
%S 13,345,673,7257,28428,184145,866944,4737473,23297196,120376601,
%T 598856998,3032621917,15138719850,76078222215,380193902100,
%U 1904900579053,9522965707286,47655682592913,238267659404765,1191769118082757
%N Number of length n+2 0..4 arrays with the sum of medians of adjacent triples multiplied by some arrangement of +-1 equal to zero
%C Column 4 of A253129
%H R. H. Hardin, <a href="/A253125/b253125.txt">Table of n, a(n) for n = 1..84</a>
%e Some solutions for n=6
%e ..1....1....2....1....0....1....0....0....1....0....2....0....2....2....2....0
%e ..3....0....2....4....1....4....0....0....0....1....0....2....2....2....1....0
%e ..4....3....3....4....2....4....1....1....3....1....0....0....3....2....2....2
%e ..3....1....0....1....2....3....3....2....2....2....2....4....1....0....2....1
%e ..0....2....2....1....1....2....0....4....3....2....2....4....3....3....3....4
%e ..4....0....2....4....1....2....0....2....2....4....4....1....4....4....0....0
%e ..3....3....2....3....4....0....3....3....2....0....3....0....3....0....0....0
%e ..3....1....4....3....3....1....0....0....4....4....0....3....1....4....3....0
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 27 2014