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1.
We prove a theorem on the growth of nonconstant solutions of a linear differential equation. From this we obtain some uniqueness theorems concerning that a nonconstant entire function and its linear differential polynomial share a small entire function. The results in this paper improve many known results. Some examples are provided to show that the results in this paper are the best possible.  相似文献   

2.
In this paper, we prove some uniqueness theorems of entire functions and their derivatives that share an entire of function whose order is less than their order. The results in this paper improve those given by G. G. Gundersen and L. Z. Yang, J. P. Wang, J. M. Chang, and Y. Z. Zhu, X. M. Li and H. X. Yi, and others. Some examples are provided to show that the results in this paper are the best possible.  相似文献   

3.
In this paper, we study the growth of solutions of a first-order linear differential equation and that of a second-order linear differential equation. From this we obtain some uniqueness theorems of a nonconstant entire function and its first derivative having the same fixed points with the same multiplicities. The results in this paper also improve some known results. Some examples show that the results in this paper are best possible.  相似文献   

4.
In this paper, we study the growth of solutions of a first order linear differential equation. From this we verify that a conjecture given by Brück is true under the restriction of the hyper order less than 1/2, and obtain some uniqueness theorems of a nonconstant entire function and its first derivative sharing a nonzero constant CM. The results in this paper also improve some known results. Some examples show that the results in this paper are best possible. Project supported by the NSFC (NO. A0324617) and the RFDP (NO. 20060422049). Received: 20 April 2006 Revised: 4 February 2007  相似文献   

5.
In this paper, we study a uniqueness question of entire functions sharing an entire function of smaller order with their difference operators. The results in this paper extend Theorem 1.1 in [19] by Liu and Yang and deal with Question 1 in [19], where the entire functions are of finite order. Moreover, we repair certain statements in [21] by Li et al., which in turn had depended on questionable assertions of Lemma 2.6 in [20]. Examples are provided to show that the results in this paper are best possible.  相似文献   

6.
We study a uniqueness question of entire functions order with their difference operators, and deal with a question in this paper extend the corresponding results obtained by Liu Examples are provided to show that the results in this paper, in sharing an entire function of smaller posed by Liu and Yang. The results -Yang and by Liu-Laine respectively. a sense, are the best possible.  相似文献   

7.
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].  相似文献   

8.
对整代数体函数与其导函数的增长性进行了研究,得到了整代数体函数与其导函数的特征函数之间关系式,并证明了它们具有相同的级和下级,从而将亚纯函数的相应结果推广到了整代数体函数.  相似文献   

9.
In connection to a result of R. Brück,we study the uniqueness of an entire function when it shares a small function with a homogeneous differential polynomial.  相似文献   

10.
In this paper, we deal with the problem of uniqueness of entire or meromorphic functions and obtain some results that are improvements over those of M. Ozawa, H. Ueda, K. Shibazaki and Yi Hongxun. An example shows that the results in this paper are sharp. Supported by the National Natural Science Foundation of China.  相似文献   

11.
We propose an entire space polynomial-time algorithm for linear programming. First, we give a class of penalty functions on entire space for linear programming by which the dual of a linear program of standard form can be converted into an unconstrained optimization problem. The relevant properties on the unconstrained optimization problem such as the duality, the boundedness of the solution and the path-following lemma, etc, are proved. Second, a self-concordant function on entire space which can be used as penalty for linear programming is constructed. For this specific function, more results are obtained. In particular, we show that, by taking a parameter large enough, the optimal solution for the unconstrained optimization problem is located in the increasing interval of the self-concordant function, which ensures the feasibility of solutions. Then by means of the self-concordant penalty function on entire space, a path-following algorithm on entire space for linear programming is presented. The number of Newton steps of the algorithm is no more than $O(nL\log (nL/ {\varepsilon }))$ , and moreover, in short step, it is no more than $O(\sqrt{n}\log (nL/{\varepsilon }))$ .  相似文献   

12.
Summary Growth properties of entire functions represented by Taylor series or Dirichlet series have been studied in this paper by considering a positive, non decreasing and unbounded function. The results thus obtained are applicable to entire functions of slow growth also. A number of earlier results have been improved in this paper.Finally, the authors wish to thank the referee for his helpful suggestions and comments.  相似文献   

13.
14.
In this paper we prove that given any two disjoint balls in an infinite dimensional complex Banach space, there exists an entire function which is bounded on one and unbounded on the other.  相似文献   

15.
The paper discusses the best or optimal uniform approximation problem by entire functions on a closed angle Δ. This problem has been studied by M.V. Keldysch in [4], under the assumption that the functions ? subject to approximation are holomorphic in a larger angle containing Δ and there is no restriction on the growth of ? at infinity. In [8], the problem was investigated for a wider class of functions ? continuously complex differentiable on Δ, with sharper estimates on the growth of approximating entire functions, linked with the growth of ? on Δ and the differential properties of ? on the boundary of Δ. In this paper, we improve some of the results on entire approximation on angles, using new approximation ideas partially presented in [9] and [10].  相似文献   

16.
By using both the Pólya theorem on the connection between the growth of an entire exponential function and the location of singularities of its Borel transform and the analog of this result for finite-order entire functions (due to Mclntyre), we obtain estimates for the indicator of the growth of an entire function in terms of its Taylor coefficients and, in some cases, determine this indicator exactly.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 45, No. 6, pp. 854–858, June, 1993.  相似文献   

17.
假设G=(V,E,F)是一个平面图。如果e1e2G中两条相邻边且在关联的面的边界上连续出现,那么称e1e2面相邻。图G的一个弱完备k-染色是指存在一个从VEFk色集合{1, …, K}的映射,使得任意两个相邻点,两个相邻面,两条面相邻的边,以及VEF中任意两个相关联的元素都染不同的颜色。若图G有一个弱完备k-染色,则称G是弱完备k-可染的。平面图G的弱完备色数是指G是弱完备k-可染的正整数k的最小值,记成χvefG)。2016年,Fabrici等人猜想:每个无环且无割边的连通平面图是弱完备7-可染的。证明外平面图满足猜想,即外平面图是弱完备7-可染的。  相似文献   

18.
In this paper we study the relationships between the spaces of entire mappings of bounded type, entire mappings of nuclear bounded type, entire mappings of Pietsch integral bounded type, and entire mappings of Grothendieck integral bounded type. Several results due to Alencar (Proc. Roy. Irish Acad.85A (1985) 131-138) and Cilia and Gutiérrez (J. Aust. Math. Soc.76 (2004) 269-280) for homogeneous polynomials are extended to entire mappings. In the main result we prove that an entire mapping is of nuclear bounded type if and only if it factors through an entire mapping of Pietsch integral bounded type.  相似文献   

19.
This study addresses Bezout equations over bivariate polynomial matrices, where the relationship between two variables is described by a real entire function. This paper proposes a solution method that makes optimal use of minor primeness to reduce such Bezout equations to simple equations over univariate scalar polynomials. The proposed solution method requires only matrix calculations, thus making it very useful, especially in the absence of modern computer algebra systems.  相似文献   

20.
A theorem of Pólya shows that the function 2 Z is the ‘smallest’ transcendental entire function that is integer valued on the set ℕ of non-negative integers. Analogous results have been established in which ℕ is replaced by other sets of integers, beginning with the result of Gel’fond for geometric sequences of integers. Other results consider the imposition of additional congruence conditions on the value sequence of the candidate entire function on the subject sequence. The present paper extends the consideration of such congruence conditions from ℕ and geometric sequences to more general sets for which Pólya-type results have been established.  相似文献   

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