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%I #5 Mar 31 2012 12:36:45
%S 1,25,125,2019,17031,259811,2809217,38543397,461143387,6074619247,
%T 75861583015,986136042011,12563765990869,162856252154639,
%U 2096257481229633,27196201756710491,352145117477485743
%N Number of zero-sum nX3 -1..1 arrays with every element equal to at least one horizontal or vertical neighbor
%C Column 3 of A201847
%H R. H. Hardin, <a href="/A201842/b201842.txt">Table of n, a(n) for n = 1..52</a>
%e Some solutions for n=5
%e .-1.-1..1...-1..0..1....1..0..0....1.-1.-1....0..0..0....1..0..0...-1.-1.-1
%e ..0..0..1...-1..0..1....1..0.-1....1..0..0....0..0..0....1..1..1....1.-1..1
%e ..0..1..1...-1..0..1....0.-1.-1....1.-1..0....0.-1..0...-1.-1..1....1.-1..1
%e .-1..0..0....0..0..1....0.-1.-1....0.-1.-1....1.-1..0...-1.-1.-1....0.-1..1
%e .-1..0..0...-1.-1..1....1..1..1....0..1..1....1..0..0....0..0..0....0..0..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Dec 06 2011
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