


Paper's Title:
On Singular Numbers of Hankel Matrices of Markov Functions
Author(s):
Vasily A. Prokhorov
Department of Mathematics and Statistics,
University of South Alabama,
Mobile, Alabama 366880002,
USA.
Email: prokhoro@southalabama.edu
URL:
http://www.southalabama.edu/mathstat/people/prokhorov.shtml
Abstract:
Let E ⊂ (01,1) be a compact set and let μ be a positive Borel measure with support supp μ=E. Let
In the case when E=[a,b]⊂ (1,1) and μ satisfies the condition dμ/dx>0 a.e. on E, we investigate asymptotic behavior of singular numbers σ_{kn,n} of the Hankel matrix D_{n}, where k_{n}/n→θ∈[0,1] as n→∞. Moreover, we obtain asymptotics of the Kolmogorov, Gelfand and linear kwidths, k=k_{n}, of the unit ball A_{n,2} of P_{n}∩L_{2}(Γ) in the space L_{2}(μ,E), where Γ={z:z=1} and P_{n} is the class of all polynomials of the degree at most n.
Paper's Title:
On Certain Classes of Harmonic Univalent Functions Based on Salagean Operator
Author(s):
G. Murugusundaramoorthy, Thomas Rosy, and B. A. Stephen
Department of Applied Mathematics and Informatics,
Department of Mathematics, Vellore Institute of Technology,
Deemed University, Vellore  632014, India.
gmsmoorthy@yahoo.com
Department of Applied Mathematics and Informatics,
Department of Mathematics, Madras Christian College,
Chennai  600059, India.
drthomasrosy@rediffmail.com
Abstract:
We define and investigate a class of complexvalued harmonic univalent functions of the form f = h + g using Salagean operator where h and g are analytic in the unit disc U = { z : z < 1 }. A necessary and sufficient coefficient conditions are given for functions in these classes. Furthermore, distortion theorems, inclusion relations, extreme points, convolution conditions and convex combinations for this family of harmonic functions are obtained.
Paper's Title:
Properties of Certain Multivalent Functions Involving Ruscheweyh Derivatives
Author(s):
NEng Xu and DingGong Yang
Department of Mathematics,
Changshu Institute of Technology,
Changshu, Jiangsu 215500,
China
Abstract:
Let A_{p}(p∈ N) be the class of functions which are analytic in the unit disk. By virtue of the Ruscheweyh derivatives we introduce the new subclasses C_{p}(n,α,β,λ,μ) of A_{p}. Subordination relations, inclusion relations, convolution properties and a sharp coefficient estimate are obtained. We also give a sufficient condition for a function to be in C_{p}(n,α,β,λ,μ)
Paper's Title:
Polyanalytic Functions on Subsets of Z[i]
Author(s):
Abtin Daghighi
Linköping University,
SE581 83,
Sweden.
Email: abtindaghighi@gmail.com
Abstract:
For positive integers q we consider the kernel of the powers L^{q} where L is one of three kinds of discrete analogues of the CauchyRiemann operator. The first two kinds are wellstudied, but the third kind less so. We give motivations for further study of the third kind especially since its symmetry makes it more appealing for the cases q≥ 2.
From an algebraic perspective it makes sense that the chosen multiplication on the kernels is compatible with the choice of pseudopowers. We propose such multiplications together with associated pseudopowers. We develop a prooftool in terms of certain sets of uniqueness.
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