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%I #6 Mar 31 2012 12:36:02
%S 704,15776,319448,7140256,159990728,3638705368,82978157360,
%T 1901358817256,43637766654744,1003656982121376,23106678843303728,
%U 532562890880016376,12282302223948007880,283443089332785590088,6543858992849366363024
%N Number of (n+1)X3 0..3 arrays with every 2X2 subblock sum equal to some horizontal or vertical neighbor 2X2 subblock sum
%C Column 2 of A185571
%H R. H. Hardin, <a href="/A185569/b185569.txt">Table of n, a(n) for n = 1..63</a>
%e Some solutions for 5X3
%e ..2..2..2....0..2..0....2..2..2....2..0..2....2..0..0....0..2..0....0..2..0
%e ..2..0..2....2..0..2....0..1..2....2..0..2....2..3..0....2..0..2....0..2..0
%e ..2..2..0....0..0..2....2..2..2....2..2..2....2..0..0....0..2..0....0..0..0
%e ..1..1..1....1..1..1....2..2..2....1..1..2....1..3..3....2..3..2....1..3..1
%e ..3..2..3....2..2..2....0..1..0....3..2..2....3..3..1....1..0..1....2..1..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 31 2011