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%I #7 Feb 07 2014 19:24:13
%S 1540,13924,126848,1200450,11356368,107575258,1019532240,9677144372,
%T 91828244608,870656179420,8257010060008,78380260564790,
%U 743849267283708,7052992728980384,66890881275269768,634973419568809332
%N Number of (n+1) X (2+1) 0..3 arrays with the maximum plus the upper median plus the lower median minus the minimum of every 2 X 2 subblock differing from its horizontal and vertical neighbors by exactly one.
%C Column 2 of A237403.
%H R. H. Hardin, <a href="/A237400/b237400.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=3
%e ..1..0..0....2..3..1....0..2..1....1..2..3....2..1..0....2..0..2....2..0..1
%e ..1..3..1....0..2..0....2..3..2....2..3..3....2..2..1....2..2..1....2..2..2
%e ..0..2..1....3..1..2....2..3..1....1..3..1....3..1..3....1..0..3....0..1..1
%e ..2..1..2....2..3..0....3..3..1....2..2..3....2..1..3....1..2..0....2..1..2
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 07 2014