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A188516 Number of nX2 binary arrays without the pattern 1 1 0 diagonally, vertically or horizontally 16

%I #14 Jun 21 2016 13:36:54

%S 4,16,49,144,400,1089,2916,7744,20449,53824,141376,370881,972196,

%T 2547216,6671889,17472400,45751696,119793025,313644100,821166336,

%U 2149898689,5628600576,14736017664,38579637889,101003196100,264430435984

%N Number of nX2 binary arrays without the pattern 1 1 0 diagonally, vertically or horizontally

%C Column 2 of A188523

%H R. H. Hardin, <a href="/A188516/b188516.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n)=4*a(n-1)-2*a(n-2)-6*a(n-3)+4*a(n-4)+2*a(n-5)-a(n-6).

%F Conjecture: a(n) = (F(n)+3) - 1)^2, where F = A000045 (Fibonacci numbers). - _Clark Kimberling_, Jun 21 2016

%F Assuming the conjecture, define b(1) = 1 and b(n) = a(n-1) for n > 1. Then b(n) = Sum{F(i,j): (i=n and 1<=j<=n) or (j=n and 1<=i<=n)}, where F is the Fibonacci fusion array, A202453. - _Clark Kimberling_, Jun 21 2016

%F G.f. for (b(n)): -x*(-1+x^3-2*x^2) / ( (x-1)*(1+x)*(x^2-3*x+1)*(x^2+x-1) ). - _R. J. Mathar_, Dec 20 2011

%F b(n) = -2*(-1)^n/5 - 2*Fibonacci(n+2) + Lucas(2*n+4)/5 + 1. - _Ehren Metcalfe_, Mar 26 2016

%e Some solutions for 3X2

%e ..0..1....0..1....0..0....0..0....1..0....0..1....1..0....0..1....0..0....0..1

%e ..0..0....0..0....0..0....0..1....1..1....1..0....0..1....0..1....1..0....1..0

%e ..1..1....0..0....0..1....1..0....1..1....0..0....1..0....1..1....0..0....0..1

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 02 2011

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Last modified April 23 16:40 EDT 2024. Contains 371916 sequences. (Running on oeis4.)