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The ω-inequality problem for concatenation hierarchies of star-free languages

  • Jorge Almeida ORCID logo EMAIL logo , Ondřej Klíma and Michal Kunc
Published/Copyright: September 6, 2017

Abstract

The problem considered in this paper is whether an inequality of ω-terms is valid in a given level of a concatenation hierarchy of star-free languages. The main result shows that this problem is decidable for all (integer and half) levels of the Straubing–Thérien hierarchy.


Communicated by Manfred Droste


Award Identifier / Grant number: UID/MAT/00144/2013

Award Identifier / Grant number: UID/MAT/00144/2013

Award Identifier / Grant number: UID/MAT/00144/2013

Award Identifier / Grant number: UID/MAT/00144/2013

Funding statement: The first author was partially supported by CMUP (UID/MAT/00144/2013), which is funded by FCT (Portugal) with national (MCTES) and European structural funds (FEDER), under the partnership agreement PT2020. The second and third authors were partially supported by the grant 15-02862S of the Grant Agency of the Czech Republic.

Acknowledgements

The authors wish to thank the anonymous referee for comments that helped improving the presentation of the paper.

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Received: 2016-2-1
Revised: 2017-5-23
Published Online: 2017-9-6
Published in Print: 2018-5-1

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