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SIGN OF FOURIER COEFFICIENTS OF MODULAR FORMS OF HALF-INTEGRAL WEIGHT

Published online by Cambridge University Press:  17 May 2016

Yuk-kam Lau
Affiliation:
Department of Mathematics, The University of Hong Kong, Pokfulam Road, Hong Kong email yklau@maths.hku.hk
Emmanuel Royer
Affiliation:
Université Clermont Auvergne, Université Blaise Pascal, Laboratoire de Mathématiques, BP 10448, F-63000 Clermont-Ferrand, France CNRS, UMR 6620, LM, F-63178 Aubière, France email emmanuel.royer@math.univ-bpclermont.fr
Jie Wu
Affiliation:
School of Mathematics, Shandong University, Jinan, Shandong 250100, China CNRS, Institut Élie Cartan de Lorraine, UMR 7502, Université de Lorraine, F-54506 Vandœuvre-lès-Nancy, France Université de Lorraine, Institut Élie Cartan de Lorraine, UMR 7502, F-54506 Vandœuvre-lès-Nancy, France email jie.wu@univ-lorraine.fr
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Abstract

We establish lower bounds for (i) the numbers of positive and negative terms and (ii) the number of sign changes in the sequence of Fourier coefficients at squarefree integers of a half-integral weight modular Hecke eigenform.

Type
Research Article
Copyright
Copyright © University College London 2016 

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