Noncommutative Polynomials Describing Convex Sets

Foundations of Computational Mathematics - The free closed semialgebraic set $${mathcal {D}}_f$$ determined by a hermitian noncommutative polynomial $$fin {text {M}}_{{delta }}({mathbb...     

Inequalities for Entire Functions of Finite Degree and Polynomials

The extremal properties of polynomials and entire functions of finite degree not vanishing in the upper half-plane are studied. The exact inequalities obtained complement and strengthen the results by Genchev, Gardner and Govil, Turan, and Lax. Proofs are based on a univalence condition established by Dubinin. Bibliography: 15 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 314, 2004, pp. 174–195.     

有穷级整函数的差分多项式的性质

考虑了差分多项式f(z)n(f(z)m-1)dΠj=1f(z+cj)vj-α(z)的零点问题,其中f(z)是有穷级的超越整函数.cj(cj≠0,j=1,…,d)是互相判别的常数,n,m,d,vj(j=1,…,d)∈N+,α(z)是f(z)的小函数.还讨论了差分多项式的唯一性问题.     

On the Approximation of Functions by Polynomials and Entire Functions of Exponential Type

Ukrainian Mathematical Journal - We present a brief survey of works in the approximation theory of functions known to the author and connected with V. K. Dzyadyk’s research works.     

Two Inequalities for Convex Functions

Let a ₀ < a ₁ < ··· < a _n be positive integers with sums $ {\sum\nolimits_{i = 0}^n {\varepsilon _{i} a_{i} {\left( {\varepsilon _{i} = 0,1} \right)}} } Let a ₀ < a ₁ < ··· < a _n be positive integers with sums distinct. P. Erd?s conjectured that The best known result along this line is that of Chen: Let f be any given convex decreasing function on [A, B] with α ₀, α ₁, ... , α _n , β ₀, β ₁, ... , β _n being real numbers in [A, B] with α ₀ ≤ α ₁ ≤ ··· ≤ α _n , Then In this paper, we obtain two generalizations of the above result; each is of special interest in itself. We prove: Theorem 1 Let f and g be two given non-negative convex decreasing functions on [A, B], and α ₀, α ₁, ... , α _n , β ₀, β ₁, ... , β _n , α' ₀, α' ₁, ... , α' _n , β' ₀ , β' ₁ , ... , β' _n be real numbers in [A, B] with α ₀ ≤ α ₁ ≤ ··· ≤ α _n , α' ₀ ≤ α' ₁ ≤ ··· ≤ α' _n , Then Theorem 2 Let f be any given convex decreasing function on [A, B] with k ₀, k ₁, ... , k _n being nonnegative real numbers and α ₀, α ₁, ... , α _n , β ₀, β ₁, ... , β _n being real numbers in [A, B] with α ₀ ≤ α ₁ ≤ ··· ≤ α _n , Then      

具两个公共小函数的整函数的唯一性

主要得到整函数与其导函数具两个公共小函数时的一个唯一性定理,改进了Rubel-Yang及郑稼华等人的某些结果。     

整函数分担多项式的增长性的进一步估计

运用正规族理论将整函数分担多项式增长级的结果进一步精确化估计.同时举例说明的结果是有意义的.     

有限级超越整函数的差分多项式的值分布

研究了差分多项式H(z)=POk∑(i=1)a_if(z+c_i)的值分布,其中f是有限级超越整函数,P(f)是,的多项式,κ≥2,ci(i=1,…,k)是互不相同的常数,α_i(i=1,…,κ)是非零常数.得到了H(z)-a和H(z)-α(z)的零点的个数的估计,其中a∈C且α(z)(■0)为小函数.讨论了H(z)的非零有限Borel例外值的不存在性.     

凸函数的两个性质的控制证明

利用受控理论给出有关凸函数的两个性质的新颖而简洁的证明.     

有限级超越整函数的(微-)差分多项式的零点分布

作者研究了有限级超越整函数的差分多项式和微-差分多项式的零点分布,在一定条件下得到了这些多项式的零点收敛指数的精确估计.所得结果可视为Hayman关于Picard例外值的经典结果的(微-)差分模拟.     

凸函数的双参数Jensen不等式链

使用组合理论,将凸函数的单参数Jensen不等式链推广为双参数的形式,从而获得一个新的Jensen不等式链.     

Fast Growth Entire Functions Whose Escaping Set Has Hausdorff Dimension Two

The authors study a family of transcendental entire functions which lie outside the Eremenko-Lyubich class in general and are of infinity growth order. Most importantly, the authors show that the intersection of Julia set and escaping set of these entire functions has full Hausdorff dimension. As a by-product of the result, the authors also obtain the Hausdorff measure of their escaping set is infinity.     

整函数与其两个导数CM共享一个值

该文研究了与两个导数共享一个非零、有穷值的整函数的唯一性问题，给出了函数确定的表达式，回答了仪洪勋，杨重骏提出的一个问题     

An Approach to the Determination of the Resultant of Two Entire Functions

We calculate the sum of the values of an entire function at the zeros of the other entire function by means of the formula of logarithmic residue. As a result, we can answer the question whether these functions have common zeros or not. Thus, we developed an approach to the determination of the resultant of two entire functions.     

Invariant Spaces of Entire Functions

Mathematical Notes - Subspaces of the space of analytic functions on a convex domain in the complex plane that are invariant with respect to the differentiation operator are studied. The problem of...