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  • Yuk-kam Lau (a1), Emmanuel Royer (a2) (a3) and Jie Wu (a4) (a5) (a6)


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.



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