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A208071 Number of 6 X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

%I A208071 #8 Jun 27 2018 15:30:04
%S A208071 16,256,324,1764,7056,26244,108900,435600,1726596,6937956,27751824,
%T A208071 110880900,443776356,1775105424,7099410564,28399664484,113598657936,
%U A208071 454386542724,1817562348900,7270249395600,29080932870276,116323860905316
%N A208071 Number of 6 X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.
%C A208071 Row 6 of A208069.
%H A208071 R. H. Hardin, <a href="/A208071/b208071.txt">Table of n, a(n) for n = 1..210</a>
%F A208071 Empirical: a(n) = 2*a(n-1) + 4*a(n-2) + 17*a(n-3) - 2*a(n-4) - 4*a(n-5) - 16*a(n-6) for n>8.
%F A208071 Empirical g.f.: 4*x*(4 + 56*x - 63*x^2 - 45*x^3 - 522*x^4 + 36*x^5 + 32*x^6 + 448*x^7) / ((1 - x)*(1 - 4*x)*(1 + x + x^2)*(1 + 2*x + 4*x^2)). - _Colin Barker_, Jun 27 2018
%e A208071 Some solutions for n=4:
%e A208071 ..0..1..0..1....1..0..1..1....1..0..0..1....0..0..1..1....1..0..0..1
%e A208071 ..0..0..1..0....0..1..0..0....0..1..1..0....0..1..0..0....0..1..1..0
%e A208071 ..0..1..0..1....0..0..1..1....1..0..0..1....0..0..1..1....1..0..0..1
%e A208071 ..0..0..1..0....0..1..0..0....0..1..1..0....0..1..0..0....0..0..1..0
%e A208071 ..0..1..0..0....0..0..1..0....1..0..0..1....0..0..1..1....1..0..0..1
%e A208071 ..0..0..1..0....0..1..0..0....0..0..1..0....0..1..0..0....0..0..1..0
%Y A208071 Cf. A208069.
%K A208071 nonn
%O A208071 1,1
%A A208071 _R. H. Hardin_, Feb 23 2012