Research output: Contribution to journal › Article › peer-review
Abelian closures of infinite binary words. / Puzynina, Svetlana; Whiteland, Markus A.
In: Journal of Combinatorial Theory. Series A, Vol. 185, 105524, 01.2022.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Abelian closures of infinite binary words
AU - Puzynina, Svetlana
AU - Whiteland, Markus A.
N1 - Publisher Copyright: © 2021 Elsevier Inc.
PY - 2022/1
Y1 - 2022/1
N2 - Two finite words u and v are called Abelian equivalent if each letter occurs equally many times in both u and v. The abelian closure A(x) of (the shift orbit closure of) an infinite word x is the set of infinite words y such that, for each factor u of y, there exists a factor v of x which is abelian equivalent to u. The notion of an abelian closure gives a characterization of Sturmian words: among binary uniformly recurrent words, Sturmian words are exactly those words for which A(x) equals the shift orbit closure Ω(x). In this paper we show that, contrary to larger alphabets, the abelian closure of a uniformly recurrent aperiodic binary word which is not Sturmian contains infinitely many minimal subshifts.
AB - Two finite words u and v are called Abelian equivalent if each letter occurs equally many times in both u and v. The abelian closure A(x) of (the shift orbit closure of) an infinite word x is the set of infinite words y such that, for each factor u of y, there exists a factor v of x which is abelian equivalent to u. The notion of an abelian closure gives a characterization of Sturmian words: among binary uniformly recurrent words, Sturmian words are exactly those words for which A(x) equals the shift orbit closure Ω(x). In this paper we show that, contrary to larger alphabets, the abelian closure of a uniformly recurrent aperiodic binary word which is not Sturmian contains infinitely many minimal subshifts.
KW - Abelian equivalence
KW - Infinite words
KW - Sturmian words
KW - Subshifts
KW - COMPLEXITY
UR - http://www.scopus.com/inward/record.url?scp=85113446454&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/73f4f5ad-b435-346e-b852-b7953422f534/
U2 - 10.1016/j.jcta.2021.105524
DO - 10.1016/j.jcta.2021.105524
M3 - Article
AN - SCOPUS:85113446454
VL - 185
JO - Journal of Combinatorial Theory - Series A
JF - Journal of Combinatorial Theory - Series A
SN - 0097-3165
M1 - 105524
ER -
ID: 86499228