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Mostrando ítems 141-150 de 509
Artículo
Holomorphic functions having large images under the action of differential operators
(Elsevier, 1999-02-15)
We prove in this note that, given a simply connected domain G in the complex plane and a sequence of infinite order linear differential operators generated by entire functions of subexponential type satisfying suitable ...
Artículo
Lineability in sequence and function spaces
(Polish Academy of Sciences, Institute of Mathematics, 2017)
It is proved the existence of large algebraic structures –including large vector subspaces or infinitely generated free algebras– inside, among others, the family of Lebesgue measurable functions that are surjective in a ...
Artículo
Approximation and entropy numbers of composition operators
(De Gruyter, 2020-10-17)
We give a survey on approximation numbers of composition operators on the Hardy space, on thedisk and on the polydisk, and add corresponding new results on their entropy numbers, revealing how theyare different.
Artículo
Compact composition operators on the Dirichlet space and capacity of sets of contact points
(Elsevier, 2013-02-15)
We prove several results about composition operators on the Dirichlet space D⁎. For every compact set K⊆∂D of logarithmic capacity , there exists a Schur function φ both in the disk algebra A(D) and in D⁎ such that the ...
Artículo
The limit relations between generalized orthogonal polynomials
(Elsevier, 1997-09)
We consider the different limit transitions for modifications of the classical polynomials obtained by the addition of one or two point masses at the ends of the interval of orthogonality. The connections between Jacobi, ...
Artículo
Compositional universality in the N-dimensional ball
(De Gruyter, 2007-05)
It is proved in this note that a sequence of automorphisms on the N-dimensional unit ball acts properly discontinuously if and only if its corresponding sequence of composition operators is universal on the Hardy space of ...
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
Driven and damped double sine-Gordon equation: The influence of internal modes on the soliton ratchet mobility
(2009)
This work studies the damped double sine-Gordon equation driven by a biharmonic force, where a parameter λ controls the existence and the frequency of an internal mode. The role of internal oscillations of the kink width ...
Artículo
Some revisited results about composition operators on Hardy spaces
(European Mathematical Society, 2012)
We generalize, on one hand, some results known for composition operators on Hardy spaces to the case of Hardy-Orlicz spaces HΨ: construction of a “slow” Blaschke product giving a non-compact composition operator on ...
Artículo
Boundary-chaotic behaviour of continuous functions under the action of operators
(Cambridge University Press, 2003-06)
In this paper we introduce two classes of operators on spaces of continuous functions with values in F-spaces under the action of which many functions behave chaotically near the boundary. Several examples, including ...