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arXiv · 2110.02615

On Hecke-type double-sums and general string functions for the affine Lie algebra $A_{1}^{(1)}$

Eric T. Mortenson
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Abstract

We demonstrate how formulas that express Hecke-type double-sums in terms of theta functions and Appell--Lerch functions -- the building blocks of Ramanujan's mock theta functions -- can be used to give general string function formulas for the affine Lie algebra $A_{1}^{(1)}$ for levels $N=1,2,3,4$.

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Eric T. Mortenson. 2021-10-06. On Hecke-type double-sums and general string functions for the affine Lie algebra $A_{1}^{(1)}$. https://doi.org/10.1007/s11139-023-00737-x

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