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

%I #11 Jun 23 2018 07:21:19

%S 14,196,546,3850,14896,84266,370734,1922564,8935850,44655394,

%T 212625504,1045480786,5031607126,24563900900,118782802866,

%U 578049254426,2801168057744,13612500276634,66026807997150,320661548440324

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

%C Row 7 of A207453.

%H R. H. Hardin, <a href="/A207458/b207458.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + 19*a(n-2) + 6*a(n-3) - 36*a(n-4).

%F Empirical g.f.: 14*x*(1 + 13*x + 6*x^2 - 36*x^3) / ((1 + 2*x - 4*x^2)*(1 - 3*x - 9*x^2)). - _Colin Barker_, Jun 23 2018

%e Some solutions for n=5:

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

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

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

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

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

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

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

%Y Cf. A207453.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 17 2012