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The Hydra Battle Revisited

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Rewriting, Computation and Proof

Part of the book series: Lecture Notes in Computer Science ((LNTCS,volume 4600))

Abstract

Showing termination of the Battle of Hercules and Hydra is a challenge. We present the battle both as a rewrite system and as an arithmetic while program, provide proofs of their termination, and recall why their termination cannot be proved within Peano arithmetic.

The first author’s research was supported in part by the Israel Science Foundation (grant no. 250/05).

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Author information

Authors and Affiliations

  1. School of Computer Science, Tel Aviv University, 69978 Ramat Aviv, Israel

    Nachum Dershowitz

  2. Microsoft Research, Redmond, WA 98052,  

    Nachum Dershowitz

  3. Institute of Computer Science, University of Innsbruck, Technikerstrasse 21a, A-6020 Innsbruck, Austria

    Georg Moser

Authors
  1. Nachum Dershowitz
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  2. Georg Moser
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Hubert Comon-Lundh Claude Kirchner Hélène Kirchner

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Dershowitz, N., Moser, G. (2007). The Hydra Battle Revisited. In: Comon-Lundh, H., Kirchner, C., Kirchner, H. (eds) Rewriting, Computation and Proof. Lecture Notes in Computer Science, vol 4600. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-73147-4_1

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  • DOI: https://doi.org/10.1007/978-3-540-73147-4_1

  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-73146-7

  • Online ISBN: 978-3-540-73147-4

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