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%I #8 Jul 02 2018 04:53:07
%S 9,81,351,1953,9999,52821,275769,1446381,7572429,39673377,207796977,
%T 1088500725,5701622643,29865934989,156441006369,819457342785,
%U 4292413923915,22484179383741,117774808544331,616918515422625
%N Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 0 1 0 vertically.
%C Row 4 of A208369.
%H R. H. Hardin, <a href="/A208370/b208370.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 19*a(n-2) + 23*a(n-3) - 26*a(n-4) - 38*a(n-5) + 13*a(n-6) + 15*a(n-7) - 4*a(n-8).
%F Empirical g.f.: 9*x*(1 + 8*x + 11*x^2 - 16*x^3 - 28*x^4 + 10*x^5 + 15*x^6 - 4*x^7) / ((1 + x)*(1 - 2*x - 17*x^2 - 6*x^3 + 32*x^4 + 6*x^5 - 19*x^6 + 4*x^7)). - _Colin Barker_, Jul 02 2018
%e Some solutions for n=4:
%e ..1..1..0..1....0..1..0..1....1..0..1..0....0..1..0..1....0..1..0..1
%e ..1..0..1..1....1..0..1..0....0..1..0..0....1..1..1..0....0..1..1..0
%e ..0..1..1..0....1..0..1..0....1..1..1..0....1..1..1..0....0..1..1..1
%e ..0..1..1..1....1..0..1..0....1..1..1..0....1..0..1..0....0..1..1..1
%Y Cf. A208369.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 25 2012
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