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arXiv · 1708.08783

Difference of a Hauptmodul for $\Gamma_{0}(N)$ and certain Gross-Zagier type CM value formulas

Dongxi Ye
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Abstract

In this work, we show that the difference of a Hauptmodul for a genus zero group $\Gamma_{0}(N)$ as a Hilbert modular function on $Y_{0}(N)\times Y_{0}(N)$ is a Borcherds lift of type $(2,2)$. As applications, we derive Monster denominator formula like product expansions for these Hilbert modular functions and certain Gross-Zagier type CM value formulas.

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Dongxi Ye. 2017-08-28. Difference of a Hauptmodul for $\Gamma_{0}(N)$ and certain Gross-Zagier type CM value formulas. https://arxiv.org/abs/1708.08783

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