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%I #6 Mar 31 2012 12:37:10
%S 15,256,4456,283728,10915392,1448239080,649065145152,203396423662488,
%T 222950396746461504,842104767130879914696,2305567526828592241306992,
%U 22136848571138455592306188104,737206270850592131066195723493312
%N Number of (n+1)X(n+1) 0..3 arrays with every 2X3 or 3X2 subblock having exactly two equal edges, and new values 0..3 introduced in row major order
%C Diagonal of A206238
%H R. H. Hardin, <a href="/A206230/b206230.txt">Table of n, a(n) for n = 1..16</a>
%e Some solutions for n=4
%e ..0..1..0..0..1....0..1..0..0..1....0..0..1..2..0....0..1..2..1..0
%e ..2..0..0..1..0....0..0..2..0..0....0..3..2..2..0....1..2..2..1..1
%e ..0..0..1..0..0....1..0..0..3..0....3..2..2..0..1....2..2..0..2..2
%e ..2..2..0..0..1....2..3..0..0..1....2..2..3..1..1....0..0..2..2..3
%e ..3..2..0..2..0....2..2..3..0..0....2..3..1..1..0....3..0..2..3..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 05 2012