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%I #11 Oct 22 2018 11:56:47
%S 344,2064,12408,76188,455160,2721900,16378560,100568160,600811200,
%T 3592908000,21619699200,132749971200,793070784000,4742638560000,
%U 28538002944000,175229961984000,1046853434880000,6260282899200000
%N Number of (n+1) X (2+1) 0..2 arrays with the maximum plus the minimum minus the upper median minus the lower median of every 2 X 2 subblock differing from its horizontal and vertical neighbors by exactly one.
%H R. H. Hardin, <a href="/A237378/b237378.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 1320*a(n-4) for n>6.
%F Empirical g.f.: 4*x*(86 + 516*x + 3102*x^2 + 19047*x^3 + 270*x^4 - 645*x^5) / (1 - 1320*x^4). - _Colin Barker_, Oct 22 2018
%e Some solutions for n=4:
%e ..2..2..0....1..1..1....0..2..0....1..1..1....0..2..1....1..0..2....2..2..0
%e ..2..1..1....0..0..1....2..1..1....1..0..2....1..1..1....2..0..2....1..1..0
%e ..0..1..0....1..0..1....1..0..1....1..2..1....1..0..2....1..1..0....0..1..2
%e ..1..1..2....1..2..2....1..1..2....1..1..2....2..1..2....1..2..1....1..2..2
%e ..1..1..1....2..2..2....0..2..0....1..1..1....1..1..0....0..1..1....1..1..1
%Y Column 2 of A237384.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 07 2014
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