P Systems with Toxic Objects

  • Artiom Alhazov
  • Rudolf Freund
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8961)


We introduce the new concept of toxic objects, objects that must not stay idle as otherwise the computation is abandoned without yielding a result. P systems of many kinds using toxic objects allow for smaller descriptional complexity, especially for smaller numbers of rules, as trap rules can be avoided. Besides presenting a number of tiny P systems generating or accepting non-semilinear sets of (vectors of) natural numbers with very small numbers of rules, we also improve the results for catalytic and purely catalytic P systems: \(14\) rules for generating a non-semilinear vector set and \(29\) rules for generating a non-semilinear number set are sufficient when allowing only the minimal number of two and three catalysts, respectively; moreover, with using toxic objects, these numbers can be reduced to \(11\) and \(17\). Yet only \(23\) rules – without using toxic objects – are needed if we allow for using more catalysts, i.e., five for catalytic P systems and seven catalysts for purely catalytic P systems.


Natural Number Target Selection Membrane Region Register Machine Derivation Mode 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  1. 1.Institute of Mathematics and Computer ScienceAcademy of Sciences of MoldovaChişinăuMoldova
  2. 2.Faculty of InformaticsVienna University of TechnologyViennaAustria

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