Formalization of Wallis Infinite Product Formula for π and the Wallis Integral

Watase, Yasushige

doi:10.2478/forma-2025-0007

Abstract

In this article, we develop the proof of the so-called Wallis formula using the Mizar formalism. The purpose of this formalization is to complete the proof of Stirling’s formula using elementary techniques of calculus; however, the formal encoding of the Wallis-type integral is also included.

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Formalization of Wallis Infinite Product Formula for π and the Wallis Integral

Abstract

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