研究了整函数差分算子的值分布和唯一性问题。本文证明了有限序整函数$ f $当与$ \max\{ρ(α), ρ(β)\}<ρ(f) $及其差$ \mathcal{L}^n_c(f)=\sum_{j=0}^{n}a_jf(z+jc) $分担两个整函数$ α$和$ β$的集合$ \mathcal{S}=\{α(z), β(z)\} $时,得到了$ \mathcal{L}^n_c(f)\equiv f $,更重要的是得到了函数$ f $的某种形式,改进了\emph{k. Liu},\emph{X. M. Li},\emph{J. Qi, Y. Wang and Y. Gu}等,并给出了一些构造性的例子来说明$ \max\{ρ(α), ρ(β)\}<ρ(f) $在我们的主要结果中是尖锐的.还展示了实例,以表明如果$ CM $共享被$ IM $共享所取代,则主要结果的结论不再成立。
英文摘要:
Value distribution and uniqueness problems of difference operator of an entire function have been investigated in this article. This research shows that a finite ordered entire function $ f $ when sharing a set $ \mathcal{S}=\{α(z), β(z)\} $ of two entire functions $ α$ and $ β$ with $ \max\{ρ(α), ρ(β)\}<ρ(f) $ with its difference $ \mathcal{L}^n_c(f)=\sum_{j=0}^{n}a_jf(z+jc) $, then $ \mathcal{L}^n_c(f)\equiv f $, and more importantly certain form of the function $ f $ has been found. The results in this paper improve those given by \emph{k. Liu}, \emph{X. M. Li}, \emph{J. Qi, Y. Wang and Y. Gu} etc. Some constructive examples have been exhibited to show the condition $ \max\{ρ(α), ρ(β)\}<ρ(f) $ is sharp in our main result. Examples have been also exhibited to show that if $ CM $ sharing is replaced by $ IM $ sharing, then conclusion of the main results ceases to hold.
Uniqueness of entire functions concerning differential-difference polynomials sharing small functions
本文研究了差分多项式$f^{n}(z)P(f(z))L_c(f)$和$g^{n}(z)P(g(z))L_c(g)$的唯一性问题,其中$L_c(f)=f(z+c)+c_0f(z)$,$P(z)$是一个具有分担一个小函数的常次系数$m$的多项式,并引入了弱权分担和松弛权分担的概念,得到了相应的结果,改进和推广了Sahoo和Biswas(Tamkang J. Math.,\textbf{49}(2),85- 97(2018))。
Relationship between the value-sharing behavior of an entire function and its derivative, and the analytic structure of a nonlinear differential equation
On uniqueness of two meromorphic functions sharing a small function
本文研究了整函数和涉及微分多项式分担一个小函数的亚纯函数的唯一性问题。我们的结果从根本上推广和改进了Bhoosnurmath-Pujari和Harina-Anand的结果,不仅用小函数代替不动点,而且降低了$ n $的下界.作者Harina-Anand在论文中犯了很多错误。我们以更方便的方式纠正了所有这些错误。最后提出了一些有待进一步研究的问题。
Set shared by an entire function with its $k$-th derivatives using normal families
本文研究了非常数整函数$ f $与它的$ k $阶导数$ f^{(k)} $共享一个集合$ \mathcal{S}=\{a,b,c\} $的问题,其中$ a, b $和$ c $是任意三个不同的复数.我们发现了\textit{Chang-Fang-Zalcman} \cite{Cha & Fan & al-ADM-2007}的主要结果的表述中的一个空白,并借助于\textit{Chang-Fang-Zalcman}所使用的方法,我们将\textit{Chang-Fang-Zalcman}的结果推广到一个更紧凑的形式.作为应用,我们利用集合共享的思想推广了著名的Br $\ddot{u}$ ck猜想\cite{Bru-1996}.