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A235673 Number of (n+1) X (2+1) 0..1 arrays with the difference between each 2 X 2 subblock maximum and minimum lexicographically nondecreasing columnwise and nonincreasing rowwise.

%I A235673 #8 Oct 19 2018 08:08:40
%S A235673 58,380,2456,15790,101398,650928,4178316,26820102,172154058,
%T A235673 1105028596,7092994476,45528746034,292241404878,1875848682364,
%U A235673 12040758823136,77287616186486,496096276240318,3184358988382152,20439867526684676
%N A235673 Number of (n+1) X (2+1) 0..1 arrays with the difference between each 2 X 2 subblock maximum and minimum lexicographically nondecreasing columnwise and nonincreasing rowwise.
%H A235673 R. H. Hardin, <a href="/A235673/b235673.txt">Table of n, a(n) for n = 1..210</a>
%F A235673 Empirical: a(n) = 8*a(n-1) - 9*a(n-2) - 9*a(n-3) + 10*a(n-4) + 3*a(n-5) - 2*a(n-6).
%F A235673 Empirical g.f.: 2*x*(29 - 42*x - 31*x^2 + 42*x^3 + 11*x^4 - 8*x^5) / ((1 - x)*(1 - x - x^2)*(1 - 6*x - 3*x^2 + 2*x^3)). - _Colin Barker_, Oct 19 2018
%e A235673 Some solutions for n=5:
%e A235673 ..0..0..0....1..1..0....0..1..0....1..1..1....1..0..1....0..0..1....1..1..0
%e A235673 ..1..0..1....1..0..0....0..1..1....1..0..0....0..0..1....1..0..1....0..1..1
%e A235673 ..0..1..1....1..0..1....0..0..1....1..0..1....0..0..0....0..1..1....1..0..0
%e A235673 ..1..0..0....0..1..0....1..1..1....1..1..1....0..0..1....0..0..0....1..1..0
%e A235673 ..0..0..1....1..0..1....1..0..1....1..0..1....0..0..0....0..0..1....0..0..1
%e A235673 ..1..1..1....0..1..1....1..1..1....1..0..1....0..0..0....0..0..1....1..1..0
%Y A235673 Column 2 of A235679.
%K A235673 nonn
%O A235673 1,1
%A A235673 _R. H. Hardin_, Jan 13 2014