Iterative Variable Elimination in ASP

  • Ricardo Gonçalves
  • Matthias KnorrEmail author
  • João Leite
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10423)


In recent years, a large variety of approaches for forgetting in Answer Set Programming (ASP) have been proposed, in the form of specific operators, or classes of operators, following different principles and obeying different properties. A recent comprehensive overview of existing operators and properties provides a uniform picture of the landscape, including many novel results on relations between properties and operators. In this paper, we introduce four new properties not considered previously and show that these are indeed succinct and relevant additions providing novel results and insights, further strengthening established relations between existing operators. Most notably among these, the invariance to permutations of the order of forgetting a set of atoms iteratively raises interesting questions with surprising results.



This work was partially supported by Fundação para a Ciência e a Tecnologia (FCT) under UID/CEC/04516/2013, and grants SFRH/BPD/100906/2014 (R. Gonçalves) and SFRH/BPD/86970/2012 (M. Knorr).


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Ricardo Gonçalves
    • 1
  • Matthias Knorr
    • 1
    Email author
  • João Leite
    • 1
  1. 1.NOVA LINCS, Departamento de Informática, Faculdade de Ciências e TecnologiaUniversidade Nova de LisboaCaparicaPortugal

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