%I #5 Mar 31 2012 12:36:46
%S 1,13,123,1205,12287,135179,1493247,16814401,192346557,2225951035,
%T 26017190841,306761764259,3644115496927,43571997337907,
%U 523947428428811,6331638407455241,76845558853198515,936178097032511349
%N Number of zero-sum nX2 -3..3 arrays with every element equal to at least one horizontal or vertical neighbor
%C Column 2 of A202134
%H R. H. Hardin, <a href="/A202131/b202131.txt">Table of n, a(n) for n = 1..73</a>
%e Some solutions for n=5
%e ..2..2....2..2...-3.-3....2..1....1..1...-2.-2....1..1....2.-3...-3.-1....1..2
%e .-1.-1....1.-2....3..3....2..1....3..0....2.-3...-3.-3....2.-3...-3.-1....1..2
%e ..2..2....1.-2....2..2....0..0....3..0....2.-3....1..2...-1.-1....1..2....0..0
%e ..0..0....1.-1...-2..2...-2.-1...-2.-2....1..2....1..2....2..2....1..2....0.-2
%e .-3.-3...-1.-1...-2.-2...-2.-1...-2.-2....1..2...-1.-1....0..0....1..1...-2.-2
%K nonn
%O 1,2
%A _R. H. Hardin_ Dec 11 2011
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