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%I #8 Mar 31 2012 12:36:54
%S 12,28,120,356,1472,4780,20228,68724,296256,1034008,4501388,15995228,
%T 69888012,251506724,1098929960,3991711796,17408141792,63681484600,
%U 276945484748,1018750420536,4416760710356,16320495059248,70538020856288
%N Number of nX2 0..3 arrays with row sums equal and column sums unequal to adjacent columns
%C Column 2 of A203031
%H R. H. Hardin, <a href="/A203026/b203026.txt">Table of n, a(n) for n = 1..210</a>
%e Some.solutions.for.n=5
%e ..3..0....3..0....2..2....3..0....0..1....3..2....3..0....1..2....0..1....1..0
%e ..1..2....3..0....1..3....1..2....1..0....2..3....2..1....2..1....0..1....0..1
%e ..3..0....3..0....1..3....1..2....1..0....3..2....3..0....3..0....1..0....0..1
%e ..0..3....0..3....1..3....3..0....0..1....2..3....2..1....3..0....0..1....1..0
%e ..2..1....2..1....2..2....1..2....0..1....2..3....3..0....0..3....0..1....0..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Dec 27 2011