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%I #5 Mar 31 2012 12:36:36
%S 1,6,36,212,1324,8342,53302,343710,2232322,14582218,95702528,
%T 630544704,4168091856,27630031358,183604587444,1222672695812,
%U 8157398577024,54515075729370,364861668341252,2445239266293460,16407415704050100
%N Number of -3..3 arrays x(0..n-1) of n elements with zero sum and no two consecutive zero elements
%C Column 3 of A199530
%H R. H. Hardin, <a href="/A199525/b199525.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions for n=5
%e ..3...-2...-3...-1....0....1....3...-2....1....3...-2....0....1....2...-3....3
%e .-3....1....2....1....2....3....0....0...-3....3....0...-3...-3....1...-1...-2
%e ..2....1...-3....0...-2...-1....1....2....0...-3...-1....1....2...-2....3....1
%e .-3....3....3....1...-2...-1...-3...-2...-1....0....3....2....1...-3...-2...-2
%e ..1...-3....1...-1....2...-2...-1....2....3...-3....0....0...-1....2....3....0
%K nonn
%O 1,2
%A _R. H. Hardin_ Nov 07 2011