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A208690 Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 0 1 vertically.

%I A208690 #9 Jul 05 2018 13:53:24
%S A208690 9,81,189,927,2889,11727,40581,154359,554733,2062215,7512453,27700479,
%T A208690 101402109,372809655,1367107173,5021003151,18423673101,67639822407,
%U A208690 248247487989,911283026751,3344800820445,12277727839863,45065827217925
%N A208690 Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 0 1 vertically.
%C A208690 Row 4 of A208688.
%H A208690 R. H. Hardin, <a href="/A208690/b208690.txt">Table of n, a(n) for n = 1..210</a>
%F A208690 Empirical: a(n) = a(n-1) + 10*a(n-2) + 2*a(n-3) - 10*a(n-4).
%F A208690 Empirical g.f.: 9*x*(1 + 8*x + 2*x^2 - 10*x^3) / (1 - x - 10*x^2 - 2*x^3 + 10*x^4). - _Colin Barker_, Jul 05 2018
%e A208690 Some solutions for n=4:
%e A208690 ..1..0..1..0....1..1..1..0....0..1..1..0....1..1..0..0....1..0..1..0
%e A208690 ..1..1..1..0....1..0..1..1....0..1..0..0....1..1..1..0....1..0..1..0
%e A208690 ..1..0..1..0....1..0..1..0....0..1..0..1....1..1..0..1....1..0..1..0
%e A208690 ..1..0..1..0....1..0..1..0....0..1..0..0....0..1..0..0....0..1..1..0
%Y A208690 Cf. A208688.
%K A208690 nonn
%O A208690 1,1
%A A208690 _R. H. Hardin_, Mar 01 2012