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arXiv · 2403.09277

Folding $π$

Michael Assis
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Abstract

It is well known that the set of origami constructible numbers is larger than the classical straight-edge and compass constructible numbers. However, the Huzita-Justin-Hatori origami constructible numbers remain algebraic so that the transcendental number $π$ can only be approximated using a finite number of straight line folds. Using these methods we give a convergent sequence for folding $π$ as well as other methods to approximate $π$. Folding along curved creases, however, allows for the construction of transcendental numbers. We here give a method to construct $π$ exactly by folding along a parabola, and we discuss generalizations for folding other transcendental numbers such as $Γ(1/4)$.

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Michael Assis. 2025-05-24. Folding $π$. https://arxiv.org/abs/2403.09277

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