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arXiv · 1702.05827

Improved lower bounds for the Mahler measure of the Fekete polynomials

Tamás Erdélyi
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Abstract

We show that there is an absolute constant $c > 1/2$ such that the Mahler measure of the Fekete polynomials $f_p$ of the form $$f_p(z) := \sum_{k=1}^{p-1}{\left( \frac kp \right)z^k}\,,$$ (where the coefficients are the usual Legendre symbols) is at least $c\sqrt{p}$ for all sufficiently large primes $p$. This improves the lower bound $\left(\frac 12 - \varepsilon\right)\sqrt{p}$ known before for the Mahler measure of the Fekete polynomials $f_p$ for all sufficiently large primes $p \geq c_{\varepsilon}$. Our approach is based on the study of the zeros of the Fekete polynomials on the unit circle.

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Tamás Erdélyi. 2017-02-20. Improved lower bounds for the Mahler measure of the Fekete polynomials. https://arxiv.org/abs/1702.05827

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