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arXiv · 1308.6477

Turán type inequalities for some Lommel functions of the first kind

Árpád Baricz·Stamatis Koumandos
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Abstract

In this paper certain Turán type inequalities for some Lommel functions of the first kind are deduced. The key tools in our proofs are the infinite product representation for these Lommel functions of the first kind, a classical result of G. Pólya on the zeros of some particular entire functions, and the connection of these Lommel functions with the so-called Laguerre-Pólya class of entire functions. Moreover, it is shown that in some cases J. Steinig's results on the sign of Lommel functions of the first kind combined with the so-called monotone form of l'Hospital's rule can be used in the proof of the corresponding Turán type inequalities.

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BibTeXRIS

Árpád Baricz, Stamatis Koumandos. 2013-08-29. Turán type inequalities for some Lommel functions of the first kind. https://doi.org/10.1017/s0013091515000413

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