Using Automata and a Decision Procedure to Prove Results in Pattern Matching (Invited Talk)

Author Jeffrey Shallit

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Jeffrey Shallit
  • School of Computer Science, University of Waterloo, Canada

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Jeffrey Shallit. Using Automata and a Decision Procedure to Prove Results in Pattern Matching (Invited Talk). In 33rd Annual Symposium on Combinatorial Pattern Matching (CPM 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 223, pp. 2:1-2:3, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)


The first-order theory of automatic sequences with addition is decidable, and this means that one can often prove combinatorial properties of these sequences "automatically", using the free software Walnut written by Hamoon Mousavi. In this talk I will explain how this is done, using as an example the measure of minimize size string attractor, introduced by Kempa and Prezza in 2018. Using the logic-based approach, we can also prove more general properties of string attractors for automatic sequences. This is joint work with Luke Schaeffer.

Subject Classification

ACM Subject Classification
  • Mathematics of computing → Combinatorics on words
  • Theory of computation → Regular languages
  • Theory of computation → Logic and verification
  • finite automata
  • decision procedure
  • automatic sequence
  • Thue-Morse sequence
  • Fibonacci word
  • string attractor


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