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Now showing items 61-70 of 71
Article
Estimates with A∞ weights for various singular integral operators
(Zanichelli, 1994)
Si studia la limitazione di certe classi di integrale singolari sullo spazio Lp(w), w € A∞.
Article
On the q-polynomials on the exponential lattice x(s)= c 1 qs + c 3
(Taylor & Francis, 1999)
The main goal of this paper is to continue the study of the q-polynomials on non-uniform lattices by using the approach introduced by Nikiforov and Uvarov in 1983. We consider the q-polynomials on the non-uniform exponential ...
Article
The τ-fixed point property for nonexpansive mappings
(1998)
Let X be a Banach space and τ a topology on X. We say that X has the τ-fixed point property (τ-FPP) if every nonexpansive mapping T defined from a bounded convex τ-sequentially compact subset C of X into C has a fixed ...
Article
The product formula
(Universitat de Barcelona, 1991)
A useful property of the Brouwer degree relates the degree of a composition of maps to the degree of each map. This property, which can be generalized for the Leray Schauder degree and in some cases for the A-proper maps ...
PhD Thesis
Espacios hiperconvexos y teoría métrica del punto fijo
(1998)
El objetivo inicial de esta Memoria fue la búsqueda de teoremas de existencia de puntos fijos para aplicaciones condensantes en espacios métricos hiperconvexos. La idea de plantearnos este problema la motivó la lectura de ...
Article
Endpoint estimates for commutators of singular integral operators
(Elsevier, 1995-02-15)
We prove endpoint estimates for commutatotrs of singular integrals with BMO functions. We first show that they satisfy L(log L) type inequalities and then that there is a Hardy space type estimate where the usual atomic ...
Article
Convergence of weighted sums of random variables and uniform integrability concerning the weights
(Universitat de Barcelona, 1994)
Let {ank}, n, k ∈ N be an array of real constants, and let {Xn} be a sequence of random variables. The concept of {ank}-uniform integrability of {Xn} is defined and two characterizations of this concept are established. ...
Article
Two-weight, weak-type norm inequalities for singular integral operators
(International Press, 1999)
We give a sufficient condition for singular integral operators and, more generally, Calder´on-Zygmund operators to satisfy the weak (p, p) inequality u({x ∈ R n : |T f(x)| > t}) ≤ C / tp Z Rn |f|p v dx, 1 < p < ∞. Our ...
Article
Two weighted inequalities for potential and fractional type maximal operators
(Indiana University, 1994)
Article
Modified Clebsch-Gordan-type expansions for products of discrete hypergeometric polynomials
(Elsevier, 1998-03-09)
Starting from the second-order difference hypergeometric equation satisfied by the set of discrete orthogonal polynomials ∗pn∗, we find the analytical expressions of the expansion coefficients of any polynomial rm(x) and ...