show/hide this revision's text 2 added 1 characters in body

The Fibonacci word is one of the Sturmian words, so its complexity is $n+1$, that is the number of different subwords of length $n$ is $n+1$. So most words are not subwords of the Fibonacci word. There are, as far as I remember 12 different but equivalent definitions of Sturmian words. Some of them give restrictions on possible subwords (see Algebraic combinatorics on words by LothairLothaire, and an article by Berstel there).

show/hide this revision's text 1

The Fibonacci word is one of the Sturmian words, so its complexity is $n+1$, that is the number of different subwords of length $n$ is $n+1$. So most words are not subwords of the Fibonacci word. There are, as far as I remember 12 different but equivalent definitions of Sturmian words. Some of them give restrictions on possible subwords (see Algebraic combinatorics on words by Lothair, and an article by Berstel there).