%I #6 Mar 31 2012 12:36:39
%S 20,80,212,594,1928,6780,23674,80750,271000,909282,3082640,10545846,
%T 36174576,123964062,424595930,1456168762,5004245744,17226485764,
%U 59361633214,204702938074,706403203606,2439664629760,8432567247356
%N Number of -2..2 arrays x(0..n+2) of n+3 elements with zero sum and no two or three adjacent elements summing to zero
%C Column 2 of A200430
%H R. H. Hardin, <a href="/A200424/b200424.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions for n=3
%e .-2....2...-1...-1....2...-2....0...-1....2....2....2...-1....1...-1....1....0
%e .-2...-1....0...-2....1...-2...-1...-2...-1....1....1....0....2....0....0...-1
%e ..0...-2....2....0...-2....1....2...-2....2....0....0...-2....1...-2...-2....0
%e ..1...-2....0....1....0....2....1....1....0...-2...-2...-1...-2....0...-2...-2
%e ..2....1....1....1...-1....0....0....2...-1...-2....0....2...-1....1....1....1
%e ..1....2...-2....1....0....1...-2....2...-2....1...-1....2...-1....2....2....2
%K nonn
%O 1,1
%A _R. H. Hardin_ Nov 17 2011