Automated Reasoning

Volume 5195 of the series Lecture Notes in Computer Science pp 162-170

LEO-II - A Cooperative Automatic Theorem Prover for Classical Higher-Order Logic (System Description)

  • Christoph BenzmüllerAffiliated withDep. of Computer Science, Saarland University
  • , Lawrence C. PaulsonAffiliated withComputer Laboratory, The University of Cambridge
  • , Frank TheissAffiliated withDep. of Computer Science, Saarland University
  • , Arnaud FietzkeAffiliated withMax Planck Institute for Informatics,  

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LEO-II is a standalone, resolution-based higher-order theorem prover designed for effective cooperation with specialist provers for natural fragments of higher-order logic. At present LEO-II can cooperate with the first-order automated theorem provers E, SPASS, and Vampire. The improved performance of LEO-II, especially in comparison to its predecessor LEO, is due to several novel features including the exploitation of term sharing and term indexing techniques, support for primitive equality reasoning, and improved heuristics at the calculus level. LEO-II is implemented in Objective Caml and its problem representation language is the new TPTP THF language.