Some bounds for the k-generalized digamma function

Abstract

We presented some monotonicity properties for the k-generalized digamma function $\psi_{k}(h)$ and we established some new bounds for $\psi_{k}^{(s)}(h),$ $s\in \mathbb{N}\cup\{0\},$ which refine recent results

Keywords

• Gamma function
• digamma function
• polygamma function
• completely monotonic function
• asymptotic expansion
• inequalities

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