A Natural Formalization of the Mutilated Checkerboard Problem in Naproche

Authors Adrian De Lon, Peter Koepke, Anton Lorenzen

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Adrian De Lon
  • Universität Bonn, Germany
Peter Koepke
  • Universität Bonn, Germany
Anton Lorenzen
  • Universität Bonn, Germany

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Adrian De Lon, Peter Koepke, and Anton Lorenzen. A Natural Formalization of the Mutilated Checkerboard Problem in Naproche. In 12th International Conference on Interactive Theorem Proving (ITP 2021). Leibniz International Proceedings in Informatics (LIPIcs), Volume 193, pp. 16:1-16:11, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2021)


Naproche is an emerging natural proof assistant that accepts input in a controlled natural language for mathematics, which we have integrated with LaTeX for ease of learning and to quickly produce high-quality typeset documents. We present a self-contained formalization of the Mutilated Checkerboard Problem in Naproche, following a proof sketch by John McCarthy. The formalization is embedded in detailed literate style comments. We also briefly describe the Naproche approach.

Subject Classification

ACM Subject Classification
  • Theory of computation → Logic and verification
  • checkerboard
  • formalization
  • formal mathematics
  • controlled language


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