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%I #8 Jun 18 2018 14:09:33
%S 7,49,241,1117,4891,20953,88465,370753,1546879,6437929,26754673,
%T 111093277,461065507,1912995217,7935844129,32917778401,136534855735,
%U 566294540737,2348729268913,9741340873213,40401894006955,167564911503529
%N Number of n X 3 0..1 arrays avoiding 0 0 0 horizontally and 0 0 1 vertically.
%C Column 3 of A207088.
%H R. H. Hardin, <a href="/A207083/b207083.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) - 5*a(n-2) - 14*a(n-3) + 11*a(n-4) + 4*a(n-5) - a(n-6).
%F Empirical g.f.: x*(7 + 7*x - 18*x^2 + 14*x^3 + 3*x^4 - x^5) / ((1 - x)*(1 - 2*x - x^2)*(1 - 3*x - 5*x^2 + x^3)). - _Colin Barker_, Jun 18 2018
%e Some solutions for n=4:
%e ..0..1..1....1..1..0....0..0..1....1..1..0....1..0..0....0..0..1....0..1..1
%e ..1..1..0....0..0..1....0..1..1....1..0..1....1..0..1....1..0..0....0..1..1
%e ..1..1..1....1..1..1....0..0..1....1..0..0....1..0..1....0..0..1....0..1..1
%e ..1..0..1....1..0..0....0..0..1....0..0..1....1..0..1....0..0..1....0..1..1
%Y Cf. A207088.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 15 2012
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