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arXiv · 2111.01044

Improved Constants for Effective Irrationality Measures from Hypergeometric Functions

Paul Voutier
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Abstract

In this paper, we simplify and improve the constant, $c$, that appears in effective irrationality measures, $|(a/b)^{m/n}-p/q|>c|q|^{-(\kappa+1)}$, obtained from the hypergeometric method for $a/b$ near $1$. The dependence of $c$ on $|a|$ in our result is best possible (as is the dependence on $n$ in many cases). For some applications, the dependence of this constant on $|a|$ becomes important. We also establish some new inequalities for hypergeometric functions that are useful in other diophantine settings.

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Paul Voutier. 2021-11-01. Improved Constants for Effective Irrationality Measures from Hypergeometric Functions. https://doi.org/10.2140/moscow.2022.11.161

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