与其导数分担三个小函数的亚纯函数

主要得到亚纯函数与其导数分担三个小函数时的一个唯一性定理.     

MEROMORPHIC FUNCTIONS SHARING TWO FINITE SETS

Let S1 ＝ {∞} and S2 ＝ {w: Ps(w)＝ 0}, Ps(w) being a uniqueness polynomial under some restricted conditions. Then, for any given nonconstant meromorphic function f, there exist at most finitely many nonconstant meromorphic functions g such that f-1(Si) ＝ g-1(Si)(i ＝ 1,2), where f-1(Si) and g-1(Si) denote the pull-backs of Si considered as a divisor, namely, the inverse images of Si counted with multiplicities, by f and g respectively.     

Uniqueness of entire function sharing a small function with its derivative

This paper is devoted to studying the relationship between an entire function and its derivative when they share one small function. We generalize some previous results of Gundersen and Yang [G. Gundersen, L.Z. Yang, Entire functions that share one value with one or two of their derivatives, J. Math. Anal. Appl. 223 (1998) 85–95], Chang and Zhu [J. Chang, Y. Zhu, Entire functions that share a small function with their derivatives, J. Math. Anal. Appl. 351 (2009) 491–496].     

Meromorphic functions sharing two sets

In the paper we discuss the uniqueness problem for meromorphic functions that share two sets and prove five theorems which improve and supplement some results earlier given by Yi and Yang [13], Lahiri and Banerjee [5].     

Unicity of meromorphic functions and their derivatives

In this paper, we prove that if a transcendental meromorphic function f shares two distinct small functions CM with its kth derivative f^(k) (k>1), then f=f^(k). We also resolve the same question for the case k=1. These results generalize a result due to Frank and Weissenborn.     

Meromorphic functions sharing three weighted values

In this paper, we deal with the relation between the characteristics of two meromorphic functions that share three weighted values, which improve the results of Q.C. Zhang. And through the results, two conjectures which proposed by Mues and Osgood-Yang are solved in a weaker condition.     

Meromorphic functions with weighted sharing of three values

In this article we study the problem of uniqueness of meromorphic functions with weighted sharing of three values. The results in this article improve some theorems of M. Ozawa, H. Ueda, G. Brosch, H. Yi, I. Lahiri and other authors. Examples are provided to show that the conditions of our results are sharp.     

具有重值分担的亚纯函数

在考虑重值分担的情况下,得到一个具有三个分担值的亚纯函数的唯一性定理及若干推论,推广并改进了仪洪勋、Lah iri等人的结果.     

Meromorphic functions sharing values in an angular domain

In this paper we study the problems of meromorphic functions sharing values in an angular domain and obtain some uniqueness results which are the improvement of the well-known five-value theorem and four-value theorem given by Nevanlinna.     

Weighted sharing of meromorphic functions relative to small functions

Using the idea of weighted sharing, we prove some results on uniqueness of meromorphic functions with three weighted sharing values. The results in this paper improve those given by H.X. Yi, T.C. Alzahary and H.X. Yi, T.C. Alzahary, I. Lahiri and N. Mandal, and other authors.     

亚纯函数及其n阶导数权分担两个值

研究亚纯函数及其n阶导数权分担两个值的唯一性问题.得到了：如果两个非常数亚纯函数f,g分担（∞,∞）,f（n）与g（n）分担（1,0）,n（≥0）为一整数,且满足C0：=（4n＋6）λ＋δn＋1（0,f）＋δn＋1（0,g）＋δn＋2（0,f）＋δn＋2（0,g）＋δn（0,f）〉4n＋10,其中λ=max{min{Θ（∞,f）,Θ（0,f）},min{Θ（∞,g）,Θ（0,g）}},那么f（n）·g（n）≡1,或者f≡g.该结果改进了前人的有关定理.     

具三个公共小函数的亚纯函数

讨论具三个公共小函数的亚纯函数的唯一性问题,其结果推广并改进了H.Ueda的一个定理。     

Value sharing of meromorphic functions and their derivatives

In this paper, we estimate the size of ρn's in the famous L. Zalcman's lemma. With it, we obtain some uniqueness theorems for meromorphic functions f and f^′ when they share two transcendental meromorphic functions.     

Entire functions that share a small function with its derivative

In this paper, by studying the properties of meromorphic functions which have few zeros and poles, we find all the entire functions f(z) which share a small and finite order meromorphic function a(z) with its derivative, and f(n)(z)−a(z)=0 whenever f(z)−a(z)=0 (n?2). This result is a generalization of several previous results.     

Uniqueness of meromorphic functions concerning sharing two small functions with their derivatives

In this paper, we study the uniqueness of meromorphic functions that share two small functions with their derivatives. We prove the following result: Let $f$ be a nonconstant meromorphic function such that $\mathop {\overline{\lim}}\limits_{r\to\infty} \frac{\bar{N}(r,f)}{T(r,f)}<\frac{3}{128}$, and let $a$, $b$ be two distinct small functions of $f$ with $a\not\equiv\infty$ and $b\not\equiv\infty$. If $f$ and $f"$ share $a$ and $b$ IM, then $f\equiv f"$.     

Small functions and uniqueness of meromorphic functions

We discuss the uniqueness of meromorphic functions sharing three weighted values and provide a complete answer to a question of T.C. Alzahary.     

Meromorphic functions sharing small functions

Let f and g be meromorphic functions sharing four small functions a₁, a₂, a₃, a₄ a_1, a_2, a_3, a_4 ignoring multiplicities. If there is a small function a₅a_5 distinct from a_j, j=1, 2, 3, 4, a_j, j=1, 2, 3, 4, such that [`(N)](r,f=a<sub>5</sub>=g) 1 S(r,f) overline {N}(r,f=a_5=g)ne S(r,f) , then f=g f=g , where [`(N)](r,f=a₅=g) overline{N}(r,f=a_5=g) is the counting function of those common zeros of f(z)-a₅(z) f(z)-a_5(z) and g(z)-a₅(z) g(z)-a_5(z) counted only once ignoring multiplicities.     

涉及小函数的亚纯函数

是否可以将第二基本定理的一般形式中常数替换为小函数,这一直是人们试图解决的重大问题.该文研究了涉及小函数的第二基本定理的推广问题, 并利用主要结果得到了几个惟一性定理, 改进了张庆德, Toda N和姚卫红等人的有关定理.     

Meromorphic functions sharing four small functions

It is well known that if two nonconstant meromorphic functions f and g on the complex plane ? have the same inverse images counted with multiplicities for four distinct values, then g is a Möbius transformation of f. In this paper, we will show that the above result remains valid if f and g share four distinct small functions counted with multiplicities truncated by 2. This is the best possible truncation level.     

亚纯函数及其导数的唯一性

本文研究具有特殊亏函数关系的亚纯函数及其k阶导数CM或IM分担小函数集合的唯一性,推广了先前已知的一些结果．