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arXiv · 2103.14861

Continued Fractions, Quadratic Fields, and Factoring: Some Computational Aspects

Michele Elia
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Abstract

Legendre discovered that the continued fraction expansion of $\sqrt N$ having odd period leads directly to an explicit representation of $N$ as the sum of two squares. In this vein, it was recently observed that the continued fraction expansion of $\sqrt N$ having even period directly produces a factor of composite $N$. It is proved here that these apparently fortuitous occurrences allow us to propose and apply a variation of Shanks' infrastructural method which significantly reduces the asymptotic computational burden with respect to currently used factoring techniques.

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Michele Elia. 2021-03-27. Continued Fractions, Quadratic Fields, and Factoring: Some Computational Aspects. https://arxiv.org/abs/2103.14861

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