Polyhedra genus theorem and Euler formula: A hypermap-formalized intuitionistic proof
نویسندگان
چکیده
منابع مشابه
Polyhedra genus theorem and Euler formula: A hypermap-formalized intuitionistic proof
This article presents formalized intuitionistic proofs for the polyhedra genus theorem, the Euler formula and a sufficient condition of planarity. They are based on a hypermap model for polyhedra and on formal specifications in the Calculus of Inductive Constructions. First, a type of free maps is inductively defined from three atomic constructors. Next, a hierarchy of types defined by invarian...
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In 1938, Tarski proved that a formula is not intuitionistically valid if, and only if, it has a counter-model in the Heyting algebra of open sets of some topological space. In fact, Tarski showed that any Euclidean space Rn with n > 1 suffices, as does e.g. the Cantor space. In particular, intuitionistic logic cannot detect topological dimension in the frame of all open sets of a Euclidean spac...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2008
ISSN: 0304-3975
DOI: 10.1016/j.tcs.2008.02.012