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%I #13 Feb 25 2018 08:41:48
%S 81,277,1033,4183,17481,75907,330433,1468723,6479721,29026267,
%T 128645233,577868563,2565424761,11535912427,51246733633,230538193603,
%U 1024408886601,4609215271387,20483612959633,92170773169843,409632127625241
%N Number of (n+1) X (1+1) 0..2 arrays with the maximum plus the lower median minus the upper median minus the minimum of every 2 X 2 subblock equal.
%C Column 1 of A236809.
%H R. H. Hardin, <a href="/A236802/b236802.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) + 20*a(n-2) - 130*a(n-3) + 36*a(n-4) + 600*a(n-5) - 720*a(n-6).
%F Empirical g.f.: x*(81 - 128*x - 1972*x^2 + 4008*x^3 + 9000*x^4 - 19440*x^5) / ((1 - 2*x)*(1 - 3*x)*(1 - 6*x^2)*(1 - 20*x^2)). - _Colin Barker_, Feb 24 2018
%e Some solutions for n=5:
%e 1 2 1 2 0 2 0 2 0 2 0 0 0 2 1 1 2 2 2 1
%e 0 0 2 0 1 0 2 1 1 0 0 0 1 1 1 0 2 1 2 2
%e 0 1 1 0 2 0 2 0 2 0 1 1 2 0 1 1 1 1 2 1
%e 1 1 0 0 0 1 1 2 2 1 1 1 1 1 2 1 2 1 2 0
%e 1 2 1 0 2 2 0 2 0 0 2 2 0 2 0 0 2 0 0 1
%e 1 1 0 0 1 0 0 1 2 1 1 1 1 1 0 1 0 1 0 0
%Y Cf. A236809.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 31 2014
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