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A208383 Number of 7 X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 1 vertically. 1

%I #8 Jul 02 2018 09:01:42

%S 14,196,216,1200,4416,14976,60984,231744,851400,3276624,12438144,

%T 46737936,177585096,673147200,2544020136,9639951936,36515578944,

%U 138204393264,523395873000,1982108510304,7504603109784,28417632893376

%N Number of 7 X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 1 vertically.

%C Row 7 of A208379.

%H R. H. Hardin, <a href="/A208383/b208383.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + 4*a(n-2) + 21*a(n-3) + 14*a(n-4) - 5*a(n-5) + 25*a(n-6) for n>8.

%F Empirical g.f.: 2*x*(7 + 91*x - 18*x^2 - 47*x^3 - 980*x^4 - 725*x^5 + 375*x^6 - 1250*x^7) / (1 - x - 4*x^2 - 21*x^3 - 14*x^4 + 5*x^5 - 25*x^6). - _Colin Barker_, Jul 02 2018

%e Some solutions for n=4:

%e ..1..1..0..1....0..0..1..0....0..1..1..0....1..1..0..1....1..0..1..0

%e ..1..1..0..0....0..0..1..1....1..0..0..1....0..1..0..1....1..0..0..1

%e ..1..1..0..0....0..0..1..0....1..0..0..1....0..1..0..0....1..0..0..1

%e ..1..1..0..0....0..0..1..0....1..0..0..1....0..1..0..0....1..0..0..1

%e ..1..1..0..0....0..0..1..0....1..0..0..1....0..1..0..0....1..0..0..1

%e ..1..1..0..0....0..0..1..0....1..0..0..1....0..1..0..0....1..0..0..1

%e ..1..1..0..0....0..0..1..0....1..0..0..1....0..1..0..0....1..0..0..1

%Y Cf. A208379.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 25 2012

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Last modified April 25 01:35 EDT 2024. Contains 371964 sequences. (Running on oeis4.)