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A231376 Number of n X 2 0..1 arrays with no element less than a strict majority of its horizontal and vertical neighbors.

%I A231376 #8 Mar 18 2018 06:59:19
%S A231376 2,10,21,48,113,261,601,1390,3216,7435,17190,39751,91921,212555,
%T A231376 491510,1136570,2628207,6077470,14053561,32497507,75147355,173771026,
%U A231376 401828790,929190453,2148663614,4968578109,11489359399,26568039511,61436038272
%N A231376 Number of n X 2 0..1 arrays with no element less than a strict majority of its horizontal and vertical neighbors.
%C A231376 Column 2 of A231382.
%H A231376 R. H. Hardin, <a href="/A231376/b231376.txt">Table of n, a(n) for n = 1..210</a>
%F A231376 Empirical: a(n) = 3*a(n-1) - 2*a(n-2) + 2*a(n-3) - 2*a(n-4) - a(n-5) for n>6.
%F A231376 Empirical g.f.: x*(2 + 4*x - 5*x^2 + x^3 - 5*x^4 - 2*x^5) / (1 - 3*x + 2*x^2 - 2*x^3 + 2*x^4 + x^5). - _Colin Barker_, Mar 18 2018
%e A231376 Some solutions for n=3:
%e A231376 ..1..0....0..1....0..0....1..0....0..0....1..0....0..0....0..1....0..0....0..0
%e A231376 ..1..0....0..0....1..1....0..0....0..0....1..0....0..1....0..1....0..0....1..1
%e A231376 ..0..0....0..0....1..1....0..0....0..0....1..0....0..1....0..1....1..1....0..0
%Y A231376 Cf. A231382.
%K A231376 nonn
%O A231376 1,1
%A A231376 _R. H. Hardin_, Nov 08 2013