Symmetry, Integrability and Geometry: Methods and Applications (SIGMA)

SIGMA 21 (2025), 087, 18 pages           https://doi.org/10.3842/SIGMA.2025.087

Bilateral Two-Parameter Mock Theta Functions and Related Applications

Chun Wang
Department of Mathematics, Shanghai Normal University, Shanghai, 200234, P.R. China

Received January 20, 2025, in final form October 06, 2025; Published online October 17, 2025

Abstract
In this paper, we investigate new relationships for bilateral series related to two-parameter mock theta functions, which lead to many identities concerning the bilateral mock theta functions. In addition, interesting relations between the classical mock theta functions and the bilateral series are also concluded.

Key words: mock theta functions; theta series; bilateral series; Appell-Lerch sums.

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