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A208103 Number of n X 3 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

%I A208103 #8 Mar 06 2018 14:59:20
%S A208103 6,36,78,171,406,990,2485,6328,16290,42195,109746,286146,747253,
%T A208103 1953276,5108806,13367035,34982430,91564278,239684565,627447600,
%U A208103 1642590586,4300214691,11257876378,29473127866,77161043541,202009252500
%N A208103 Number of n X 3 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.
%C A208103 Column 3 of A208108.
%H A208103 R. H. Hardin, <a href="/A208103/b208103.txt">Table of n, a(n) for n = 1..210</a>
%F A208103 Empirical: a(n) = 4*a(n-1) - 2*a(n-2) - 6*a(n-3) + 4*a(n-4) + 2*a(n-5) - a(n-6) for n>7.
%F A208103 Empirical g.f.: x*(6 + 12*x - 54*x^2 - 33*x^3 + 70*x^4 + 20*x^5 - 15*x^6) / ((1 - x)*(1 + x)*(1 - 3*x + x^2)*(1 - x - x^2)). - _Colin Barker_, Mar 06 2018
%e A208103 Some solutions for n=10:
%e A208103 ..1..0..0....0..0..1....1..0..0....0..1..1....0..1..1....0..0..1....1..0..1
%e A208103 ..0..0..1....1..0..0....0..0..1....0..0..1....0..0..1....0..1..1....1..0..1
%e A208103 ..1..0..0....0..1..1....1..1..0....0..0..1....1..0..1....0..0..1....1..0..1
%e A208103 ..0..1..1....1..0..0....0..0..1....0..1..1....0..1..1....1..1..1....1..0..1
%e A208103 ..1..0..0....0..1..1....1..0..0....0..0..1....1..0..1....0..0..1....1..1..1
%e A208103 ..0..1..1....1..0..0....0..0..1....0..0..1....0..0..1....0..1..1....1..0..1
%e A208103 ..1..0..0....0..0..1....1..0..0....0..1..1....1..0..1....1..0..1....1..1..1
%e A208103 ..0..0..1....1..0..0....0..0..1....1..0..1....0..0..1....0..1..1....1..0..1
%e A208103 ..1..1..0....0..1..1....1..0..0....0..0..1....0..1..1....1..0..1....1..0..1
%e A208103 ..0..0..1....1..0..0....0..0..1....0..0..1....0..0..1....0..1..1....1..0..1
%Y A208103 Cf. A208108.
%K A208103 nonn
%O A208103 1,1
%A A208103 _R. H. Hardin_, Feb 23 2012