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%I #4 Feb 10 2014 18:11:02
%S 1786,2356,1488,2012,2816,4440,5976,10104,14168,22294,29908,50502,
%T 70828,111468,149540,252510,354140,557340,747700,1262550,1770700,
%U 2786700,3738500,6312750,8853500,13933500,18692500,31563750,44267500,69667500
%N Number of (n+1)X(4+1) 0..2 arrays with the upper median of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one
%C Column 4 of A237637
%H R. H. Hardin, <a href="/A237633/b237633.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-4) for n>14
%e Some solutions for n=5
%e ..0..0..0..1..2....2..2..1..0..1....2..2..1..0..1....1..1..2..0..0
%e ..2..1..0..1..2....1..0..0..0..2....1..0..0..0..2....0..2..1..0..1
%e ..0..2..0..0..0....1..0..1..2..1....2..0..1..2..1....2..0..0..0..2
%e ..0..1..2..1..0....0..0..2..0..0....0..0..2..0..0....1..0..1..2..1
%e ..0..0..0..2..1....1..2..1..0..1....1..2..1..0..1....0..0..2..0..0
%e ..2..1..0..1..2....2..0..0..0..1....2..0..0..0..2....1..2..1..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 10 2014