An overlapfree word is a word that contains no contiguous substring of the form , where is a letter and is a possibly empty word. A squarefree
word is overlapfree, and an overlapfree word is cubefree.
The numbers
of binary overlapfree words of length , 2, ... are 2, 4, 6, 10, 14, 20, ... (OEIS A007777).
satisfies
(1)
for some positive constants and (Restivo and Salemi 1985, Kobayashi 1988). In addition, while
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in Mathematical
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Sequences."
, where 
is a letter and 
is a possibly empty word. A squarefree
word is overlapfree, and an overlapfree word is cubefree.
of binary overlapfree words of length 
, 2, ... are 2, 4, 6, 10, 14, 20, ... (OEIS A007777).
satisfies
and 
(Restivo and Salemi 1985, Kobayashi 1988). In addition, while
and 
(Cassaigne 1993).
