The Syntactic Complexity of Semi-flower Languages

  • Kitti Gelle
  • Szabolcs IvánEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11612)


Semi-flower languages are those of the form \(L^*\) for some finite maximal prefix code L, or equivalently, those recognizable by a so-called semi-flower automaton, in which all the cycles have a common state \(q_0\), which happens to be the initial state and the only accepting state.

We show that the syntactic complexity of these languages is exactly \(n^n-n!+n\) (where n stands for the state complexity as usual) and that this bound is reachable with an alphabet of size n.


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© IFIP International Federation for Information Processing 2019

Authors and Affiliations

  1. 1.Department of Computer ScienceUniversity of SzegedSzegedHungary

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