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%I #5 Mar 31 2012 12:37:06
%S 81,2412,205803,44160240,25618992453,37886453633808,
%T 153727495029223899,1571194548319712891100
%N Number of (n+1)X(n+1) 0..2 arrays with the number of clockwise edge increases in every 2X2 subblock differing from each horizontal or vertical neighbor
%C Diagonal of A205520
%e Some solutions for n=4
%e ..1..2..0..0..1....2..0..1..2..0....1..1..1..0..0....0..1..0..0..2
%e ..2..2..1..1..0....2..2..1..2..1....1..0..2..0..0....1..2..0..0..1
%e ..1..0..0..2..0....1..0..1..0..1....2..1..2..1..0....2..2..1..1..2
%e ..0..0..0..2..1....2..2..0..0..2....1..1..0..0..2....1..0..0..2..2
%e ..2..1..1..0..0....1..0..0..0..1....0..2..0..0..2....0..0..0..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 28 2012