Now showing items 1-20 of 452

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      2º Congreso de Jóvenes Investigadores  [Article]

      Gancedo García, Francisco; Muro Jiménez, Fernando (Real Sociedad Matematica Española, 2013)
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      A Birkhoff theorem for Riemann surfaces  [Article]

      Montes Rodríguez, Alfonso (Rocky Mountain Mathematics Consortium, 1998)
      A classical theorem of Birkhoff asserts that there exists an entire function f such that the sequence of function {/(z + n)}n≥o is dense in the space of entire functions. In this paper we give sufficient conditions on a ...
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      A Bp condition for the strong maximal function  [Article]

      Liu, Liguang; Luque Martínez, Teresa (American Mathematical Society, 2014-11)
      A strong version of the Orlicz maximal operator is introduced and a natural Bp condition for the rectangle case is defined to characterize its boundedness. This fact let us to describe a sufficient condition for the two ...
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      A characterization of the classical orthogonal discrete and q-polynomials  [Article]

      Alfaro García, Manuel; Álvarez Nodarse, Renato (Elsevier, 2007-04-01)
      In this paper we present a new characterization for the classical discrete and q-classical (discrete) polynomials (in the Hahn's sense).
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      A continuation method for weakly contractive mappings under the interior condition  [Article]

      Ariza Ruiz, David; Jiménez Melado, Antonio (Hindawi, 2009)
      Recently, Frigon proved that, for weakly contractive maps, the property of having a fixed point is invariant by a certain class of homotopies, obtaining as a consequence a Leray-Schauder alternative for this class of maps ...
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      A continuation method for weakly Kannan maps  [Article]

      Ariza Ruiz, David; Jiménez Melado, Antonio (SpringerOpen, 2010)
      The first continuation method for contractive maps in the setting of a metric space was given by Granas. Later, Frigon extended Granas theorem to the class of weakly contractive maps, and recently Agarwal and O’Regan have ...
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      A criterion of weak compactness for operators on subspaces of Orlicz spaces  [Article]

      Lefèvre, Pascal; Li, Daniel; Queffélec, Hervé; Rodríguez Piazza, Luis (Hindawi, 2008)
      We give a criterion of weak compactness for the operators on the Morse-Transue space MΨ , the subspace of the Orlicz space LΨ generated by L∞.
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      A dynamical characterization of sub-Arakelian subsets  [Article]

      Calderón Moreno, María del Carmen; Prado Bassas, José Antonio (Elsevier, 2013-09-15)
      We are going to characterize those sets which can be covered by an Arakelian set in terms of dynamical properties of entire functions via similarities. Moreover, if we consider the set of universal entire functions via ...
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      A fixed point theorem for weakly Zamfirescu mappings  [Article]

      Ariza Ruiz, David; Jiménez Melado, Antonio; López Acedo, Genaro (Elsevier, 2011-03-01)
      In [13] T. Zamfirescu, Fixed point theorems in metric spaces, Arch. Math. 23 (1972), 292–298. Zamfirescu gave a fixed point theorem that generalizes the classical fixed point theorems by Banach, Kannan and Chatterjea. In ...
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      A Fredholm mapping of index zero  [Article]

      Soriano Arbizu, José María (Korean Mathematical Society, 2008)
      Sufficient conditions are given to assert that between any two Banach spaces over K Fredholm mappings share exactly N values in a specific open ball. The proof of the result is constructive and is based upon continuation methods.
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      A generalization of the classical Laguerre polynomials  [Article]

      Álvarez Nodarse, Renato; Marcellán Español, Francisco (Springer, 1995)
      We consider a modi cation of the gamma distribution by adding a discrete measure supported in the point x = 0. For large n we analyze the existence of orthogonal polynomials with respect to such a distribution. Finally we ...
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      A geometrical coefficient implying the fixed point property and stability results  [Article]

      Domínguez Benavides, Tomás (University of Houston, 1996)
      In this paper we define a new geometric constant M(X) in Banach spaces such that X has the fixed point property for nonexpansive mappings if M(X) > 1. We prove that M(X) •_ WCS(X), the inequality being strict in many ...
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      A local spectral condition for strong compactness with some applications to bilateral weighted shifts  [Article]

      Lacruz Martín, Miguel Benito; Romero de la Rosa, María del Pilar (American Mathematical Society, 2014-01)
      An algebra of bounded linear operators on a Banach space is said to be strongly compact if its unit ball is precompact in the strong operator topology, and a bounded linear operator on a Banach space is said to be strongly ...
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      A lot of “counterexamples” to Liouville's theorem  [Article]

      Bernal González, Luis (Elsevier, 1996-08-01)
      We prove in this paper that, given α ∈ (0, 1/2), there exists a linear manifold M of entire functions satisfying that M is dense in the space of all entire functions and, in addition, limz→∞ exp(|z|α) f(j)(z) = 0 on any ...
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      A lower bound for the equilateral number of normed spaces  [Article]

      Swanepoel, Konrad J.; Villa Caro, Rafael (American Mathematical Society, 2008)
      We show that if the Banach-Mazur distance between an n-dimensional normed space X and ℓ n∞ is at most 3/2, then there exist n + 1 equidistant points in X. By a well-known result of Alon and Milman, this implies that an ...
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      A maximum principle for the Muskat problem for fluids with different densities  [Article]

      Córdoba Gazolaz, Diego; Gancedo García, Francisco (Springer, 2009-03)
      We consider the fluid interface problem given by two incompressible fluids with different densities evolving by Darcy’s law. This scenario is known as the Muskat problem for fluids with the same viscosities, being in two ...
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      A new characterization of the Muckenhoupt Ap weights through an extension of the Lorentz-Shimogaki theorem  [Article]

      Lerner, Andrei K.; Pérez Moreno, Carlos (Indiana University, 2007)
      Given any quasi-Banach function space X over Rn it is defined an index αX that coincides with the upper Boyd index αX when the space X is rearrangement-invariant. This new index is defined by means of the local maximal ...
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      A new quantitative two weight theorem for the Hardy-Littlewood maximal operator  [Article]

      Pérez Moreno, Carlos; Rela, Ezequiel (American Mathematical Society, 2015-02)
      A quantitative two weight theorem for the Hardy-Littlewood maximal operator is proved improving the known ones. As a consequence a new proof of the main results in [HP] and in [HPR12] is obtained which avoids the use of ...
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      A note on an ergodic theorem in weakly uniformly convex geodesic spaces  [Article]

      Leustean, Laurentiu; Nicolae, Adriana (Springer, 2015-11)
      Karlsson and Margulis [A. Karlsson, G. Margulis, A multiplicative ergodic theorem and nonpositively curved spaces. Commun. Math. Phys. 208 (1999), 107-123] proved in the setting of uniformly convex geodesic spaces, which ...
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      A note on interface dynamics for convection in porous media  [Article]

      Córdoba Gazolaz, Diego; Gancedo García, Francisco; Orive Illera, Rafael (Elsevier, 2008-07-15)
      We study the fluid interface problem through porous media given by two incompressible 2-D fluids of different densities. This problem is mathematically analogous to the dynamics interface for convection in porous media, ...