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arXiv · 2003.13207

Two remarks on proof theory of first-order arithmetic

Toshiyasu Arai
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Abstract

In this note let us give two remarks on proof-theory of PA. First a derivability relation is introduced to bound witnesses for provable $\Sigma_{1}$-formulas in PA. Second Paris-Harrington's proof for their independence result is reformulated to show a `consistency' proof of PA based on a combinatorial principle.

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Toshiyasu Arai. 2020-03-30. Two remarks on proof theory of first-order arithmetic. https://arxiv.org/abs/2003.13207

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