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A208380 Number of 4 X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 1 vertically.

%I A208380 #8 Jul 02 2018 08:43:54
%S A208380 8,64,108,420,1344,4212,13860,44880,144540,468852,1517184,4906980,
%T A208380 15883764,51401040,166325292,538259268,1741843392,5636673684,
%U A208380 18240740100,59028275280,191019298428,618151779156,2000381177088,6473368570500
%N A208380 Number of 4 X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 1 vertically.
%C A208380 Row 4 of A208379.
%H A208380 R. H. Hardin, <a href="/A208380/b208380.txt">Table of n, a(n) for n = 1..210</a>
%F A208380 Empirical: a(n) = a(n-1) + 4*a(n-2) + 9*a(n-3) + 5*a(n-4) - 2*a(n-5) + 4*a(n-6) for n>8.
%F A208380 Empirical g.f.: 4*x*(2 + 14*x + 3*x^2 - 4*x^3 - 31*x^4 - 22*x^5 + 12*x^6 - 16*x^7) / ((1 - 2*x - 4*x^2)*(1 + x + 2*x^2 - x^3 + x^4)). - _Colin Barker_, Jul 02 2018
%e A208380 Some solutions for n=4:
%e A208380 ..1..0..1..1....1..0..0..1....1..0..0..1....1..1..0..1....1..0..0..1
%e A208380 ..1..0..0..1....0..1..0..1....1..1..0..0....1..1..0..1....0..1..1..0
%e A208380 ..1..0..0..1....0..1..0..0....1..1..0..0....0..1..0..0....0..0..1..0
%e A208380 ..1..0..0..1....0..1..0..0....1..1..0..0....0..1..0..0....0..0..1..0
%Y A208380 Cf. A208379.
%K A208380 nonn
%O A208380 1,1
%A A208380 _R. H. Hardin_, Feb 25 2012