%I #8 Oct 22 2018 11:43:16
%S 81,344,1472,6368,27280,115584,494592,2139648,9166080,38836224,
%T 166182912,718921728,3079802880,13048971264,55837458432,241557700608,
%U 1034813767680,4384454344704,18761386033152,81163387404288,347697425940480
%N Number of (n+1) X (1+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="/A237377/b237377.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 336*a(n-4) for n>5.
%F Empirical g.f.: x*(81 + 344*x + 1472*x^2 + 6368*x^3 + 64*x^4) / (1 - 336*x^4). - _Colin Barker_, Oct 22 2018
%e Some solutions for n=5:
%e ..1..2....1..2....1..2....2..0....1..1....1..0....0..2....2..2....2..2....2..0
%e ..1..2....2..0....1..2....1..1....0..0....0..1....1..0....0..0....2..1....1..0
%e ..1..1....2..2....2..0....0..1....1..2....1..1....0..1....1..0....1..2....2..1
%e ..2..2....0..1....1..1....0..1....0..1....0..2....0..2....1..2....2..0....0..0
%e ..2..1....1..2....0..1....0..2....2..0....1..0....2..0....1..1....1..1....0..0
%e ..2..1....0..0....1..2....2..0....1..1....1..0....1..0....2..0....0..1....0..1
%Y Column 1 of A237384.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 07 2014