A length bound for binary equality words

Jana Hadravová

Commentationes Mathematicae Universitatis Carolinae (2011)

  • Volume: 52, Issue: 1, page 1-20
  • ISSN: 0010-2628

Abstract

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Let w be an equality word of two binary non-periodic morphisms g , h : { a , b } * Δ * with unique overflows. It is known that if w contains at least 25 occurrences of each of the letters a and b , then it has to have one of the following special forms: up to the exchange of the letters a and b either w = ( a b ) i a , or w = a i b j with gcd ( i , j ) = 1 . We will generalize the result, justify this bound and prove that it can be lowered to nine occurrences of each of the letters a and b .

How to cite

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Hadravová, Jana. "A length bound for binary equality words." Commentationes Mathematicae Universitatis Carolinae 52.1 (2011): 1-20. <http://eudml.org/doc/246151>.

@article{Hadravová2011,
abstract = {Let $w$ be an equality word of two binary non-periodic morphisms $g,h: \lbrace a,b\rbrace ^* \rightarrow \Delta ^*$ with unique overflows. It is known that if $w$ contains at least 25 occurrences of each of the letters $a$ and $b$, then it has to have one of the following special forms: up to the exchange of the letters $a$ and $b$ either $w=(ab)^ia$, or $w=a^ib^j$ with $\operatorname\{gcd\} (i,j)=1$. We will generalize the result, justify this bound and prove that it can be lowered to nine occurrences of each of the letters $a$ and $b$.},
author = {Hadravová, Jana},
journal = {Commentationes Mathematicae Universitatis Carolinae},
keywords = {combinatorics on words; binary equality languages; morphism; equality words; equality language; combinatorics on words},
language = {eng},
number = {1},
pages = {1-20},
publisher = {Charles University in Prague, Faculty of Mathematics and Physics},
title = {A length bound for binary equality words},
url = {http://eudml.org/doc/246151},
volume = {52},
year = {2011},
}

TY - JOUR
AU - Hadravová, Jana
TI - A length bound for binary equality words
JO - Commentationes Mathematicae Universitatis Carolinae
PY - 2011
PB - Charles University in Prague, Faculty of Mathematics and Physics
VL - 52
IS - 1
SP - 1
EP - 20
AB - Let $w$ be an equality word of two binary non-periodic morphisms $g,h: \lbrace a,b\rbrace ^* \rightarrow \Delta ^*$ with unique overflows. It is known that if $w$ contains at least 25 occurrences of each of the letters $a$ and $b$, then it has to have one of the following special forms: up to the exchange of the letters $a$ and $b$ either $w=(ab)^ia$, or $w=a^ib^j$ with $\operatorname{gcd} (i,j)=1$. We will generalize the result, justify this bound and prove that it can be lowered to nine occurrences of each of the letters $a$ and $b$.
LA - eng
KW - combinatorics on words; binary equality languages; morphism; equality words; equality language; combinatorics on words
UR - http://eudml.org/doc/246151
ER -

References

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