Feasible Automata for Two-Variable Logic with Successor on Data Words

  title={Feasible Automata for Two-Variable Logic with Successor on Data Words},
  author={Ahmet Kara and Thomas Schwentick and Tony Tan},
We introduce an automata model for data words, that is words that carry at each position a symbol from a finite alphabet and a value from an unbounded data domain. The model is (semantically) a restriction of data automata, introduced by Bojanczyk, et. al. in 2006, therefore it is called weak data automata. It is strictly less expressive than data automata and the expressive power is incomparable with register automata. The expressive power of weak data automata corresponds exactly to… 

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