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arXiv · 1209.2229

A Direct Version of Veldman's Proof of Open Induction on Cantor Space via Delimited Control Operators

Danko Ilik·Keiko Nakata
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Abstract

First, we reconstruct Wim Veldman's result that Open Induction on Cantor space can be derived from Double-negation Shift and Markov's Principle. In doing this, we notice that one has to use a countable choice axiom in the proof and that Markov's Principle is replaceable by slightly strengthening the Double-negation Shift schema. We show that this strengthened version of Double-negation Shift can nonetheless be derived in a constructive intermediate logic based on delimited control operators, extended with axioms for higher-type Heyting Arithmetic. We formalize the argument and thus obtain a proof term that directly derives Open Induction on Cantor space by the shift and reset delimited control operators of Danvy and Filinski.

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Danko Ilik, Keiko Nakata. 2014-04-22. A Direct Version of Veldman's Proof of Open Induction on Cantor Space via Delimited Control Operators. https://doi.org/10.4230/lipics.types.2013.188

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