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%I #5 Mar 31 2012 12:36:37
%S 10,40,114,426,1650,6126,23206,88636,337866,1295566,4992364,19269156,
%T 74529210,288954786,1122363984,4366362420,17011617426,66365823648,
%U 259213619826,1013542247970,3966939195402,15540399135516,60929935280508
%N Number of -2..2 arrays x(0..n+1) of n+2 elements with zero sum and no two neighbors summing to zero
%C Column 2 of A199832
%H R. H. Hardin, <a href="/A199826/b199826.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions for n=3
%e ..0....0...-1....0...-1....1...-1...-1....1....1...-1...-2....0...-2....1....1
%e ..1...-1...-2...-2....2....2....0...-2....0....2...-2....1....2...-2....1...-2
%e .-2...-1....0....0....0....1...-1....1....1....0....1....0...-1....1....0...-1
%e ..1....2....2....2....1...-2....2....1...-2...-1....2....2...-1....2...-2....2
%e ..0....0....1....0...-2...-2....0....1....0...-2....0...-1....0....1....0....0
%K nonn
%O 1,1
%A _R. H. Hardin_ Nov 11 2011
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