Results 1 to 10 of about 3,169 (164)
AN EXTREMAL PROBLEM FOR UNIVALENT FUNCTIONS [PDF]
Let S be the class of functions f(z)=z+a2z 2 …, f(0)=0, f′(0)=1 which are regular and univalent in the unit disk |z| x the equation φ′( x)=0 does not have real roots. Since S is a compact class, there exists x .
Miodrag IOVANOV
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Extremality of Koebe’s Function
The remarkable Koebe function is the (unique) extremal of many important distortion functionals in geometric function theory. This paper provides a complete characterization of such functionals.
Samuel L. Krushkal
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On the existence of an extremal function for the Delsarte extremal problem
Abstract In the general setting of a locally compact Abelian group G, the Delsarte extremal problem asks for the supremum of integrals over the collection of continuous positive definite functions $$f \colon G \to \mathbb{R}$$ f :
exaly +4 more sources
On the Existence of an Extremal Function in the Delsarte Extremal Problem [PDF]
AbstractThis paper is concerned with a Delsarte-type extremal problem. Denote by$${\mathcal {P}}(G)$$P(G)the set of positive definite continuous functions on a locally compact abelian groupG. We consider the function class, which was originally introduced by Gorbachev,$$\begin{aligned}&{\mathcal {G}}(W, Q)_G = \left\{ f \in {\mathcal {P}}(G) \cap L^
Marcell Gaál, Zsuzsanna Nagy-Csiha
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A Functional Extremal Criterion [PDF]
Let \({\mathcal N}=\{(t_k, X_k):\, k\geq 1\}\) be a point process with time space \([0, \infty)\) and state space \([0, \infty)^d\), where \(\{t_k\}\) are distinct nonrandom time points monotonically increasing to \(\infty\). \(\{X_k\}\) are independent and identically distributed random vectors on a given probability space with values in \([0,\infty ...
Jordanova, P. K., Pancheva, E. I.
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On the extremal function for graph minors [PDF]
AbstractFor a graph , let , where means that is a minor of . We show that if has average degree , then where is an explicitly defined constant. This bound matches a corresponding lower bound shown to hold for almost all such by Norin, Reed, Wood and the first author.
Andrew Thomason 0001, Matthew Wales
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Approximation of Minimal Functions by Extreme Functions [PDF]
In a recent paper, Basu, Hildebrand, and Molinaro established that the set of continuous minimal functions for the 1-dimensional Gomory-Johnson infinite group relaxation possesses a dense subset of extreme functions. The $n$-dimensional version of this result was left as an open question.
Teresa M. Lebair, Amitabh Basu
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On an Optimal Quadrature Formula in a Hilbert Space of Periodic Functions
The present work is devoted to the construction of optimal quadrature formulas for the approximate calculation of the integrals ∫02πeiωxφ(x)dx in the Sobolev space H˜2m.
Kholmat Shadimetov +2 more
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Construction of optimal interpolation formula exact for trigonometric functions by Sobolev’s method
The paper is devoted to derivation of the optimal interpolation formula in W2(0,2)(0,1) Hilbert space by Sobolev’s method. Here the interpolation formula consists of a linear combination ΣNβ=0Cβφ(xβ) of the given values of a function φ from the space ...
Shadimetov, Kh.M. +2 more
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Entropy of an extremal electrically charged thin shell and the extremal black hole
There is a debate as to what is the value of the entropy S of extremal black holes. There are approaches that yield zero entropy S=0, while there are others that yield the Bekenstein–Hawking entropy S=A+/4, in Planck units.
José P.S. Lemos +2 more
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