### Volume 7

n° 1 (2005), pp. 217-230author: | Kumar Neeraj Verma and Jean Goubault-Larrecq |
---|---|

title: | Karp-Miller Trees for a Branching Extension of VASS |

keywords: | branching vector addition systems, Karp-Miller trees, coverability, multiplicative exponential linear logic, equational tree automata |

abstract: | We study BVASS (Branching VASS) which extend VASS (Vector Addition Systems with States) by allowing addition transitions that merge two configurations. Runs in BVASS are tree-like structures instead of linear ones as for VASS. We show that the construction of Karp-Miller trees for VASS can be extended to BVASS. This entails that the coverability set for BVASS is computable. This allows us to obtain decidability results for certain classes of equational tree automata with an associative-commutative symbol. Recent independent work by de Groote et al. implies that decidability of reachability in BVASS is equivalent to decidability of provability in MELL (multiplicative exponential linear logic), which is still an open problem. Hence our results are also a step towards answering this question in the affirmative. |

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reference: | Kumar Neeraj Verma and Jean Goubault-Larrecq (2005),
Karp-Miller Trees for a Branching Extension of VASS,
Discrete Mathematics and Theoretical Computer Science 7, pp. 217-230 |

bibtex: | For a corresponding BibTeX entry, please consider our BibTeX-file. |

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Automatically produced on Thu Nov 3 22:44:23 CET 2005 by falk