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A207847 Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 1 1 1 vertically.

%I A207847 #8 Jun 25 2018 15:55:51
%S A207847 10,100,240,780,2320,7140,21600,65980,200400,610740,1857520,5656380,
%T A207847 17211840,52396900,159466800,485403660,1477389520,4496881380,
%U A207847 13687155360,41660429500,126802853520,385955704500,1174746099760,3575622750780
%N A207847 Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 1 1 1 vertically.
%C A207847 Row 4 of A207845.
%H A207847 R. H. Hardin, <a href="/A207847/b207847.txt">Table of n, a(n) for n = 1..210</a>
%F A207847 Empirical: a(n) = a(n-1) + 6*a(n-2) + a(n-3) - a(n-4) for n>5.
%F A207847 Empirical g.f.: 10*x*(1 + 9*x + 8*x^2 - 7*x^3 + x^4) / (1 - x - 6*x^2 - x^3 + x^4). - _Colin Barker_, Jun 25 2018
%e A207847 Some solutions for n=4:
%e A207847 ..1..0..1..0....1..0..1..1....0..1..1..1....1..1..1..0....0..1..0..1
%e A207847 ..0..1..0..0....1..0..1..1....1..0..1..0....1..0..1..0....1..0..1..1
%e A207847 ..1..1..1..1....0..1..0..0....0..1..0..1....0..1..0..1....0..1..0..0
%e A207847 ..1..0..1..0....0..1..0..0....1..0..1..1....1..1..1..1....1..1..0..1
%Y A207847 Cf. A207845.
%K A207847 nonn
%O A207847 1,1
%A A207847 _R. H. Hardin_, Feb 21 2012