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1.
In this article, we deal with the uniqueness problems on meromorphic functions sharing two finite sets in an angular domain instead of the whole plane C. In particular, we investigate the uniqueness for meromorphic functions of infinite order in an angular domain and obtain some results. Moreover, examples show that the conditions in theorems are necessary.  相似文献   

2.
In this article, we study the uniqueness question of nonconstant meromorphic functions whose nonlinear differential polynomials share 1 or have the same fixed points in an angular domain. The results in this article improve Theorem 1 of Yang and Hua [26], and improve Theorem 1 of Fang and Qiu [6].  相似文献   

3.
In this article, the authors study the structure of the solutions for the EuierPoisson equations in a bounded domain of Rn with the given angular velocity and n is an odd number. For a ball domain and a constant angular velocity, both existence and nonexistence theorem are obtained depending on the adiabatic gas constant 7. In addition, they obtain the monotonicity of the radius of the star with both angular velocity and center density. They also prove that the radius of a rotating spherically symmetric star, with given constant angular velocity and constant entropy, is uniformly bounded independent of the central density. This is different to the case of the non-rotating star.  相似文献   

4.
On transcendental meromorphic functions with radially distributed values   总被引:13,自引:0,他引:13  
The growth of transcendental meromorphic functions in terms of their ordersis investigated in this paper when they and their derivatives have radially distributed valuesfollowing the discussion of the author. A simple and elementary way to study such subjectsis exhibited in this paper; that is, once an estimation of B(r, *) in terms of a few c(r, **) inthe Nevanlinna theory on angular domains is established, we can produce one result thatthe order of a mermorphic function with radially distributed values related to C(r, **) canbe estimated under the assumption of existence of suitable deficient value. The results ob-tained in this paper lead us to a new singular direction in terms of Nevanlinna charactersticinstead of the order of meromorphic functions.  相似文献   

5.
Angular distribution in complex oscillation theory   总被引:5,自引:0,他引:5  
Let f_1 and f_2 be two linearly independent solutions of the differential equationf″ Af=0,where A is an entire function.Set E=f_1f_2.In this paper,we shall studythe angular distribution of E and establish a relation between zero accumulation rays andBorel directions of E.Consequently we can obtain some results in the complex differentialequation by using known results in angular distribution theory of meromorphic functions.  相似文献   

6.
Let {fn} be a sequence of meromorphic functions on a plane domain D, whose zeros and poles have multiplicity at least 3. Let {hn} be a sequence of meromorphic functions on D, whose poles are multiple, such that {hn} converges locally uniformly in the spherical metric to a function h which is meromorphic and zero-free on D.If fn≠hn, then {fn} is normal on D.  相似文献   

7.
In 1992,Yang Lo posed the following problem:let F be a family of entire functions,let D be a domain in C,and let k 2 be a positive integer.If,for every f∈F,both f and its iteration f~khave no fixed points in D,is F normal in D?This problem was solved by Ess′en and Wu in 1998,and then solved for meromorphic functions by Chang and Fang in 2005.In this paper,we study the problem in which f and f~(k ) have fixed points.We give positive answers for holomorphic and meromorphic functions.(I)Let F be a family of holomorphic functions in a domain D and let k 2 be a positive integer.If,for each f∈F,all zeros of f(z)-z are multiple and f~khas at most k distinct fixed points in D,then F is normal in D.Examples show that the conditions"all zeros of f(z)-z are multiple"and"f~k having at most k distinct fixed points in D"are the best possible.(II)Let F be a family of meromorphic functions in a domain D,and let k 2 and l be two positive integers satisfying l 4 for k=2 and l 3 for k 3.If,for each f∈F,all zeros of f(z)-z have a multiplicity at least l and f~khas at most one fixed point in D,then F is normal in D.Examples show that the conditions"l 3for k 3"and"f~k having at most one fixed point in D"are the best possible.  相似文献   

8.
In this article, we consider the singular points of meromorphic functions in the unit disk. We prove the second fundamental theorem for the Ahlfors-Shimizu’s characteristic in the unit disk in terms of Nevanlinna theory in the angular domains, and obtain the existence of T -points and Hayman T -points dealing with small functions as target.  相似文献   

9.
章文华 《数学季刊》2006,21(4):577-580
We proved:Let F be a family of meromorphic functions in a domain D and a≠0,b∈C.If f′(z)-a(f(z))~2≠b,f≠0 and the poles of f(z)are of multiplicity>=3 for each f(z)∈F,then F is normal in D.  相似文献   

10.
In this paper, discussed are the problems about uniqueness of algebroidal functions in the unit disc with share-values in a sector domain instead of the whole disk. Results are obtained extending some uniqueness theorems of meromorphic functions.  相似文献   

11.
We investigate the value distribution of meromorphic functions in the angular domain. In particular, we show a close relationship between radially distributed values and Borel directions of transcendental meromorphic functions of infinite order in some angular domains.  相似文献   

12.
利用角域Nevanlinna特征函数和亚纯函数的辐角分布理论研究了亚纯函数的角域唯一性问题,获得了一些涉及重值的角域唯一性的结果,该角域包含亚纯函数的一条Borel方向.  相似文献   

13.
拟亚纯映射的Borel方向   总被引:6,自引:0,他引:6  
宋述刚 《数学杂志》1999,19(3):277-281
对于平面上的K-拟亚纯映射时,建立了一个角域的基本不等式,由此证明了K-拟亚纯映射的Borel方向的存在性及其相应性质。  相似文献   

14.
In this paper, we investigate the uniqueness of meromorphic functions in the unit disc and consider the relation between the Borel points and shared-values of meromorphic functions in an angular domain.  相似文献   

15.
亚纯函数涉及小函数的奇异方向   总被引:1,自引:1,他引:0  
吴昭君  陈莉  孙道椿 《数学杂志》2008,28(3):271-276
本文研究了平面上亚纯函数的奇异方向.利用角域内Ahlfors-Shimize特征函数和几个已有的关于函数增长性估计的引理,证明了复平面上的零级超越亚纯函数存在一条涉及小函数的T方向.推广了吴昭君和孙道椿给出的结果.  相似文献   

16.
该文研究了复平面上的亚纯函数在角域内分担两个集合的唯一性,将仪洪勋和林伟川最近得到的复平面上的亚纯函数在全平面上分担两个集合的唯一性定理中的在全平面上分担两个集合的条件改成在角域内分担两个集合,得到了几个唯一性定理.  相似文献   

17.
In this article we investigate the uniqueness of transcendental meromorphic function dealing with four shared values in one angular domain instead of the whole complex plane.  相似文献   

18.
Meromorphic functions sharing values in an angular domain   总被引:1,自引:0,他引:1  
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.  相似文献   

19.
研究了无穷级亚纯函数f与亚纯函数g在某个角域上具有分担集S = {a1,a2,a3}的增长级关系.  相似文献   

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