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%I #5 Mar 31 2012 12:37:32
%S 2433709,5997955680,14734218092801,36208249913281496,
%T 88975418528153598168,218642562001425020608504,
%U 537278068297042230986389307,1320272420115802027617060782841
%N 1/4 the number of (n+1)X6 0..3 arrays with every 2X2 subblock having one, three or four distinct clockwise edge differences
%C Column 5 of A210156
%H R. H. Hardin, <a href="/A210153/b210153.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..3..1..1..3..2..1....1..1..3..1..0..0....3..0..0..3..0..3....2..1..1..2..1..1
%e ..1..1..0..3..2..3....1..0..2..3..2..1....2..2..0..2..2..3....0..2..0..0..0..0
%e ..3..0..0..2..2..3....1..0..3..3..0..1....0..0..1..0..3..3....2..1..1..0..2..1
%e ..2..0..1..0..2..0....0..0..3..2..3..1....3..3..1..3..1..0....0..1..0..2..2..1
%e ..1..2..1..3..0..0....1..2..0..2..0..0....0..3..0..1..1..1....0..3..1..0..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 18 2012