Cusp forms of weight 1/2 and pairs of quadratic forms

András Biró

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arXiv · 2507.02522

Cusp forms of weight 1/2 and pairs of quadratic forms

András Biró

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Abstract

We prove a spectral summation formula for the product of four Fourier coefficients of half-integral weight cusp forms in Kohnen's subspace. The other side of the formula involves certain generalized class numbers of pairs of quadratic forms with integer coefficients.

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András Biró. 2025-07-03. Cusp forms of weight 1/2 and pairs of quadratic forms. https://arxiv.org/abs/2507.02522

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