how to concatinate fibonacci sequence

Hi I want to write matlab code for fibonacci wordswhichis like

s(0)=0, s(1)=01, s(2)=010, s(3)=01001....

using formula s(n)=s(n-1)s(n-2). I have written a code but it gives error

 clear all
n(1)=0;
n(2)=01;
 k=3;
    while k<=13
        n(k)=horzcat(n(k-1),n(k-2));
        k=k+1;
    end
    n(k)

error is

In an assignment  A(:) = B, the number of elements in A and B must be the same.
Error in fibbword (line 6)
        n(k)=horzcat(n(k-1),n(k-2)); 

Answer 1

[Walter Roberson]

 n{1} = '0' ;
 n{2} = '01';
 k=3;
    while k<=13
        n{k} = horzcat(n{k-1},n{k-2});
        k=k+1;
    end
    n{end}

[Walter Roberson]

n{end}(1:256)

[sadiqa ilyas]

thanks a lot . now how to convert ' n ' into bit string. I have to xor the result into the encrypted image

[sadiqa ilyas]

and restrict to only 256 bits

[sadiqa ilyas]

Thanks a lot