Meromorphic function sharing three sets with its shift, q-shift, q-difference and analogous operators |
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Author |
abanerjee kal@yahoo.co.in, abanerjeekal@gmail.com1, saikat352@gmail.com, saikatbh89@yahoo.com2
1) Department of Mathematics, University of Kalyani
West Bengal, India; 2) Department of Mathematics, University of Kalyani
West Bengal, India
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Abstract |
Using the notion of weighted sharing of three sets we deal with the uniqueness problem of meromorphic function with its shift, q-shift, q-difference and analogous operator. A handful number of examples have been provided to substantiate our certain claims.
In other words, we deduce conditions providing
a) $f(z) \equiv t f(z+c)$, where $t^n=1$, $n\ge 2$;
b) $f(z)\equiv t f(qz+c)$, where $t^n=1$, $n\ge 2$ and $q , c \in \mathbb{C} \setminus \{0\}$;
c) $f(z)\equiv tf(qz)$, where $t^n=1$ and $\mid q \mid =1$;
d) $f(z)\equiv \chi_{_n}\Delta_qf$ for $n\ge 2$ with $\Delta_qf=f(qz)-f(z)$ and $\chi_{_n}=
\begin{cases}
1, & \mbox{if } n=2, \\
t, & \mbox{if } n \geq 3,\; t^n=1.
\end{cases}$
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Keywords |
meromorphic functions; uniqueness; shift; difference operator; shared set
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DOI |
doi:10.30970/ms.52.1.38-47
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Reference |
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Pages |
38-47
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Volume |
52
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Issue |
1
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Year |
2019
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Journal |
Matematychni Studii
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Full text of paper | |
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