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Mostrando ítems 1-10 de 14
Artículo
On the modification of classical orthogonal polynomials: the symmetric case
(Springer, 1998-03)
We consider the modifcations of the monic Hermite and Gegenbauer polynomials via the addition of one point mass at the origin. Some properties of the resulting polynomials are studied: three-term recurrence relation, ...
Artículo
Second order difference equations for certain families of discrete polynomials
(Elsevier, 1998-11-16)
In this paper we will consider two algorithms which allow us to obtain second order linear di erence equations for certain families of polynomials. The corresponding algorithms can be implemented in any computer algebra ...
Artículo
WKB approximation and Krall-Type orthogonal polynomials
(Springer, 1998-10)
We give an uni ed approach to the Krall-type polynomials orthogonal with respect to a positive measure consisting of an absolutely continuous one \perturbed" by the addition of one or more delta Dirac functions. Some ...
Artículo
A Birkhoff theorem for Riemann surfaces
(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 ...
Tesis Doctoral
Propiedades de concentración en espacios de dimensión finita Inmersiones isométricas en espacios de funciones continuas
(1998)
Esta memoria está dedicada al estudio de dos problemas del Análisis Funcional: El estudio de propiedades de concentración y su relación con la Geometría de los Espacios de Banach, englobado dentro de la Teoría Local de ...
Artículo
On regularization in superreflexive Banach spaces by infimal convolution formulas
(Polish Academy of Sciences, Institute of Mathematics, 1998)
We present here a new method for approximating functions defined on superreflexive Banach spaces by differentiable functions with α-H¨older derivatives (for some 0 < α ≤ 1). The smooth approximation is given by means of ...
Artículo
Jacobi-Sobolev-type orthogonal polynomials: second-order differential equation and zeros
(Elsevier, 1998-04-17)
We obtain an explicit expression for the Sobolev-type orthogonal polynomials {Qn} associated with the inner product 〈p,q〉=∫−11 p(x)q(x)p(x)dx + A1p(1)q(1) + B1p(−1)q(−1) + A2p′(1)q′(1) + B2p′(−1)q′(−1), where p(x) = (1 − ...
Tesis Doctoral
Estabilidad de la propiedad del punto fijo para aplicaciones no-expansivas
(1998)
La teoría métrica del punto fijo estudia la existencia de dichos puntos para aplicaciones definidas en un espacio métrico y bajo condiciones que no son invariantes al pasar a métricas equivalentes. En este aspecto, el ...
Artículo
Some extension of the Bessel-type orthogonal polynomials
(Taylor & Francis, 1998)
We consider the perturbation of the classical Bessel moment functional by the addition of the linear functional M0 (x) + M1 0 (x), where M0 and M1 2 IR. We give necessary and su cient conditions in order for this functional ...
Artículo
Approximation of Lipschitz functions by Δ-convex functions in banach spaces
(Springer, 1998-12)
In this paper we give some results about the approximation of a Lipschitz function on a Banach space by means of ∆-convex functions. In particular, we prove that the density of ∆-convex functions in the set of Lipschitz ...