Some improvements of criteria of L-index boundedness in direction |
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Author |
andriykopanytsia@gmail.com
Ivano-Frankivsk National Technical University of Oil and Gas, Ivano-Frankivsk, Ukraine
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Abstract |
In this paper,
we improve criteria of boundedness of $L$-index in direction for entire functions in $\mathbb{C}^n.$ They give an estimate of maximum modulus
on circles of various radius, maximum modulus by minimum modulus on circle and describe the behavior of directional logarithmic derivative and the distribution of zeros.
The obtained results are also new for entire functions of bounded index in $\mathbb{C}.$
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Keywords |
entire function; bounded L-index in direction; distribution of zeros; directional logarithmic derivative
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DOI |
doi:10.15330/ms.47.1.27-32
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Reference |
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Pages |
27-32
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Volume |
47
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Issue |
1
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Year |
2017
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Journal |
Matematychni Studii
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Full text of paper | |
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