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A208067 Number of n X 6 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

%I A208067 #8 Jun 27 2018 09:07:17
%S A208067 26,676,2080,6400,12960,26244,44064,73984,111520,168100,236160,331776,
%T A208067 443520,592900,763840,984064,1232064,1542564,1887840,2310400,2775520,
%U A208067 3334276,3944160,4665600,5447520,6360484,7344064,8479744,9696960
%N A208067 Number of n X 6 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.
%C A208067 Column 6 of A208069.
%H A208067 R. H. Hardin, <a href="/A208067/b208067.txt">Table of n, a(n) for n = 1..210</a>
%F A208067 Empirical: a(n) = 2*a(n-1) + 2*a(n-2) - 6*a(n-3) + 6*a(n-5) - 2*a(n-6) - 2*a(n-7) + a(n-8) for n>9.
%F A208067 Empirical g.f.: 2*x*(13 + 312*x + 338*x^2 + 522*x^3 + 28*x^4 - 76*x^5 + 26*x^6 + 26*x^7 - 13*x^8) / ((1 - x)^5*(1 + x)^3). - _Colin Barker_, Jun 27 2018
%e A208067 Some solutions for n=4:
%e A208067 ..0..1..1..0..0..1....0..0..1..0..0..1....1..1..0..1..1..0....0..1..1..0..0..1
%e A208067 ..1..0..0..1..1..0....1..1..0..0..1..0....1..0..1..1..0..1....1..0..0..1..1..0
%e A208067 ..0..0..1..0..0..1....0..0..1..0..0..1....0..1..0..0..1..0....0..1..1..0..0..1
%e A208067 ..1..0..0..1..0..0....0..1..0..0..1..0....1..0..1..0..0..1....1..0..0..1..0..0
%Y A208067 Cf. A208069.
%K A208067 nonn
%O A208067 1,1
%A A208067 _R. H. Hardin_, Feb 23 2012