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A236886 Number of (n+1) X (1+1) 0..2 arrays with the maximum plus the upper median minus the lower median minus the minimum of every 2 X 2 subblock equal. 1

%I

%S 81,245,781,2605,8901,31253,111685,406949,1503365,5632837,21327109,

%T 81569413,314366469,1220142341,4761187333,18668554757,73468028933,

%U 290057876485,1147984105477,4553121130501,18087737270277,71955008016389

%N Number of (n+1) X (1+1) 0..2 arrays with the maximum plus the upper median minus the lower median minus the minimum of every 2 X 2 subblock equal.

%H R. H. Hardin, <a href="/A236886/b236886.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 9*a(n-1) - 8*a(n-2) - 136*a(n-3) + 364*a(n-4) + 380*a(n-5) - 2080*a(n-6) + 992*a(n-7) + 2400*a(n-8) - 1920*a(n-9).

%F Empirical g.f.: x*(81 - 484*x - 776*x^2 + 8552*x^3 - 4460*x^4 - 41760*x^5 + 46992*x^6 + 46592*x^7 - 58112*x^8) / ((1 - x)*(1 - 2*x)*(1 - 4*x)*(1 - 2*x - 4*x^2)*(1 - 6*x^2)*(1 - 10*x^2)). - _Colin Barker_, Oct 21 2018

%e Some solutions for n=5:

%e ..2..0....2..1....1..1....2..2....2..0....2..2....1..2....1..2....2..1....0..1

%e ..0..1....0..2....2..0....1..0....2..1....2..1....2..0....0..1....0..2....1..2

%e ..0..2....1..0....0..0....2..0....0..0....1..1....0..1....1..0....1..2....1..0

%e ..2..1....2..0....0..2....1..0....1..2....2..1....2..0....1..0....2..0....1..0

%e ..0..2....1..2....0..0....2..2....0..0....2..2....1..0....2..1....2..1....1..2

%e ..2..1....2..0....1..1....1..0....1..2....1..2....2..0....1..0....0..2....2..1

%Y Column 1 of A236893.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 01 2014

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Last modified June 26 09:52 EDT 2022. Contains 354879 sequences. (Running on oeis4.)