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arXiv · 1912.08126

Theta lifts for Lorentzian lattices and coefficients of mock theta functions

Jan Hendrik Bruinier·Markus Schwagenscheidt
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Abstract

We evaluate regularized theta lifts for Lorentzian lattices in three different ways. In particular, we obtain formulas for their values at special points involving coefficients of mock theta functions. By comparing the different evaluations, we derive recurrences for the coefficients of mock theta functions, such as Hurwitz class numbers, Andrews' spt-function, and Ramanujan's mock theta functions.

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Jan Hendrik Bruinier, Markus Schwagenscheidt. 2020-01-07. Theta lifts for Lorentzian lattices and coefficients of mock theta functions. https://doi.org/10.1007/s00209-020-02572-y

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