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arXiv · 2512.18121

Contour Integration and Cyclotomic Ap\'ery-Like Series Involving Generalized Binomial Coefficients

Ce Xu
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Abstract

In this paper, we present a method based on contour integration to investigate a class of cyclotomic parametric Ap\'ery-like series. The general term of such series involves a parametric central binomial coefficient, which is defined via the Gamma function. Using this approach, we express a family of cyclotomic Ap\'ery-like series in terms of multiple polylogarithms, cyclotomic Hurwitz zeta values, Riemann zeta values and $\log(2)$. In particular, we provide several illustrative examples and corollaries, which enable us to recover a number of known results on Ap\'ery-like series. At the same time, we have also left open two questions regarding Ap\'ery-like series. Moreover, by considering integrals of the generating function for Fuss-Catalan numbers, we derive an alternative expression for a classical Ap\'ery-like series. Combining this with known results allows us to establish several identities for multiple polylogarithm functions.

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Ce Xu. 2025-12-19. Contour Integration and Cyclotomic Ap\'ery-Like Series Involving Generalized Binomial Coefficients. https://arxiv.org/abs/2512.18121

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