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Computing central values of twisted L-series: the case of composite levels

Ariel Pacetti·Gonzalo Tornaría
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Abstract

Let f be a newform of weight two and composite level N. We show how to compute weight 3/2 modular forms "associated" to f whose Fourier coefficients are related to the central values of quadratic twists (real and imaginary) of f. We will focus on examples for levels N=27, N=15, and N=75, which exhibit most aspects of our methods.

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Ariel Pacetti, Gonzalo Tornaría. 2006-07-01. Computing central values of twisted L-series: the case of composite levels. https://arxiv.org/abs/math/0607008

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