Geometrically convergent sequences of upper and lower bounds on the Wallis ratio and related expressions
Document Type
Article
Publication Date
2015
Department
Department of Mathematical Sciences
Abstract
Sequences of algebraic upper and lower bounds on the Wallis ratio Γ(x + 1)/Γ(x + 1/2) are given with the relative errors that converge to 0 geometrically and uniformly on any interval of the form [x0, ∞) for x0 > - 1/2 ; moreover, the relative and absolute errors converge to 0 as x→ ∞. These conclusions are based on corresponding results for the digamma function ψ := Γ′ Γ/. Relations with other relevant results are discussed, as well as the corresponding computational aspects. This work was motivated by studies of exact bounds involving the Student probability distribution.
Publication Title
Mathematical Inequalities and Applications
Recommended Citation
Pinelis, I.
(2015).
Geometrically convergent sequences of upper and lower bounds on the Wallis ratio and related expressions.
Mathematical Inequalities and Applications,
18(1), 195-205.
http://doi.org/10.7153/mia-18-14
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p/3264
Publisher's Statement
© 2015 Element. Publisher’s version of record: https://doi.org/10.7153/mia-18-14