Multiple Clausen values and deformed Ap\'ery-like series

Zhi-Wei Sun; Yajun Zhou

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arXiv · 2607.14646

Multiple Clausen values and deformed Ap\'ery-like series

Zhi-Wei Sun·Yajun Zhou

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Abstract

With generalized central binomial coefficients $ \binom{2x}{x}:=\frac{\Gamma(2x+1)}{[\Gamma(x+1)]^2}$ defined through Euler's gamma function, we represent deformed Ap\'ery-like series \[ \mathscr A_{s,n}:=\sum_{k=1}^\infty\left.\!\frac{\partial^n}{\partial x^n}\frac{1}{x^s\binom{2x}{x}}\right|_{x=k} \] by multiple Clausen values (MCVs), which belong to a special class of cyclotomic multiple zeta values (CMZVs) at level $3$. For example, exploiting provable algebraic relations among MCVs, we show that \[\mathscr A_{1,5}=-\frac{9[495L(\chi_{-3},6)-30\pi^{2}L(\chi_{-3},4)-2\pi^{4}L(\chi_{-3},2)]}{4}\]and\[\mathscr A_{4,4}=\frac{352\zeta_{5,3}}{15}+\frac{752537\pi^{8}}{10206000},\]where $ L(\chi_{-3},s):=\sum_{n=0}^\infty\left[(3n+1)^{-s}-(3n+2)^{-s}\right]$ and $\zeta_{5,3}:=\sum_{m>n>0}m^{-5}n^{-3}$.

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Zhi-Wei Sun, Yajun Zhou. 2026-07-16. Multiple Clausen values and deformed Ap\'ery-like series. https://arxiv.org/abs/2607.14646

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