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A207896 Number of 3 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 0 and 1 1 1 vertically.

%I A207896 #9 Jun 26 2018 06:09:36
%S A207896 6,36,84,198,462,1080,2520,5886,13746,32100,74964,175062,408822,
%T A207896 954720,2229552,5206662,12159090,28395060,66310836,154855350,
%U A207896 361632894,844519416,1972201800,4605672606,10755603282,25117504404,58656777396
%N A207896 Number of 3 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 0 and 1 1 1 vertically.
%C A207896 Row 3 of A207895.
%H A207896 R. H. Hardin, <a href="/A207896/b207896.txt">Table of n, a(n) for n = 1..210</a>
%F A207896 Empirical: a(n) = a(n-1) + 2*a(n-2) + 2*a(n-3) + a(n-4) + a(n-5) for n>6.
%F A207896 Empirical g.f.: 6*x*(1 + 5*x + 6*x^2 + 5*x^3 + 3*x^4 + 2*x^5) / (1 - x - 2*x^2 - 2*x^3 - x^4 - x^5). - _Colin Barker_, Jun 26 2018
%e A207896 Some solutions for n=4:
%e A207896 ..0..1..0..0....0..1..1..0....1..1..1..1....1..1..1..0....0..0..1..1
%e A207896 ..0..1..1..0....0..0..1..0....1..1..0..0....1..0..0..1....0..1..0..0
%e A207896 ..1..0..0..1....1..0..0..1....0..0..1..1....0..1..0..0....1..1..0..0
%Y A207896 Cf. A207895.
%K A207896 nonn
%O A207896 1,1
%A A207896 _R. H. Hardin_, Feb 21 2012