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A207683 Number of 3 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 1 1 vertically.

%I A207683 #8 Mar 05 2018 10:00:12
%S A207683 6,36,72,164,336,702,1488,3164,6612,13916,29532,62032,130548,275904,
%T A207683 581196,1223824,2581620,5442424,11466060,24172016,50959908,107395128,
%U A207683 226366524,477188096,1005780564,2119935656,4468615788,9419000656
%N A207683 Number of 3 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 1 1 vertically.
%C A207683 Row 3 of A207682.
%H A207683 R. H. Hardin, <a href="/A207683/b207683.txt">Table of n, a(n) for n = 1..210</a>
%F A207683 Empirical: a(n) = a(n-2) + 6*a(n-3) + 4*a(n-4) - 6*a(n-6) for n>8.
%F A207683 Empirical g.f.: 2*x*(3 + 18*x + 33*x^2 + 46*x^3 + 12*x^4 - 19*x^5 - 42*x^6 + 3*x^7) / (1 - x^2 - 6*x^3 - 4*x^4 + 6*x^6). - _Colin Barker_, Mar 05 2018
%e A207683 Some solutions for n=4:
%e A207683 ..0..1..1..1....1..1..0..0....0..1..1..1....1..0..0..1....0..0..1..0
%e A207683 ..0..1..0..0....1..0..0..1....1..1..1..0....0..0..1..1....0..1..0..0
%e A207683 ..0..0..1..0....0..1..0..0....1..0..0..1....0..0..1..0....0..0..1..0
%Y A207683 Cf. A207682.
%K A207683 nonn
%O A207683 1,1
%A A207683 _R. H. Hardin_, Feb 19 2012