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General Dirichlet series, arithmetic convolution equations and Laplace transforms

Helge Glöckner, Lutz G. Lucht, Štefan Porubský (2009)

Studia Mathematica

In the earlier paper [Proc. Amer. Math. Soc. 135 (2007)], we studied solutions g: ℕ → ℂ to convolution equations of the form a d g d + a d - 1 g ( d - 1 ) + + a g + a = 0 , where a , . . . , a d : are given arithmetic functions associated with Dirichlet series which converge on some right half plane, and also g is required to be such a function. In this article, we extend our previous results to multidimensional general Dirichlet series of the form x X f ( x ) e - s x ( s k ), where X [ 0 , ) k is an additive subsemigroup. If X is discrete and a certain solvability criterion is satisfied,...

General Franklin systems as bases in H¹[0,1]

Gegham G. Gevorkyan, Anna Kamont (2005)

Studia Mathematica

By a general Franklin system corresponding to a dense sequence of knots 𝓣 = (tₙ, n ≥ 0) in [0,1] we mean a sequence of orthonormal piecewise linear functions with knots 𝓣, that is, the nth function of the system has knots t₀, ..., tₙ. The main result of this paper is a characterization of sequences 𝓣 for which the corresponding general Franklin system is a basis or an unconditional basis in H¹[0,1].

General Haar systems and greedy approximation

Anna Kamont (2001)

Studia Mathematica

We show that each general Haar system is permutatively equivalent in L p ( [ 0 , 1 ] ) , 1 < p < ∞, to a subsequence of the classical (i.e. dyadic) Haar system. As a consequence, each general Haar system is a greedy basis in L p ( [ 0 , 1 ] ) , 1 < p < ∞. In addition, we give an example of a general Haar system whose tensor products are greedy bases in each L p ( [ 0 , 1 ] d ) , 1 < p < ∞, d ∈ ℕ. This is in contrast to [11], where it has been shown that the tensor products of the dyadic Haar system are not greedy bases in L p ( [ 0 , 1 ] d ) for 1...

General theory of the fuzzy integral.

Pietro Benvenuti, Doretta Vivona (1996)

Mathware and Soft Computing

By means of two general operations + and x, called pan-operations'', we build a new kind of integral. This formulation contains, as particular cases, both Choquet's and Sugeno's integrals.

Généralisation des algèbres de Beurling

Philippe Tchamitchian (1984)

Annales de l'institut Fourier

Cet article est consacré à l’étude des espaces A ω = L 2 ( R n ; ω ( x ) d x ) qui sont des algèbres de Banach. On démontre que les multiplicateurs ponctuels de A ω sont les fonctions qui appartiennent localement et uniformément à A ω si et seulement si A ω contient des fonctions à support compact.

Generalised functions of bounded deformation

Gianni Dal Maso (2013)

Journal of the European Mathematical Society

We introduce the space G B D of generalized functions of bounded deformation and study the structure properties of these functions: the rectiability and the slicing properties of their jump sets, and the existence of their approximate symmetric gradients. We conclude by proving a compactness results for G B D , which leads to a compactness result for the space G S B D of generalized special functions of bounded deformation. The latter is connected to the existence of solutions to a weak formulation of some variational...

Generalization of the Newman-Shapiro isometry theorem and Toeplitz operators. II

Dariusz Cichoń (2002)

Studia Mathematica

The Newman-Shapiro Isometry Theorem is proved in the case of Segal-Bargmann spaces of entire vector-valued functions (i.e. summable with respect to the Gaussian measure on ℂⁿ). The theorem is applied to find the adjoint of an unbounded Toeplitz operator T φ with φ being an operator-valued exponential polynomial.

Generalization of the topological algebra ( C b ( X ) , β )

Jorma Arhippainen, Jukka Kauppi (2009)

Studia Mathematica

We study subalgebras of C b ( X ) equipped with topologies that generalize both the uniform and the strict topology. In particular, we study the Stone-Weierstrass property and describe the ideal structure of these algebras.

Generalization of the weak amenability on various Banach algebras

Madjid Eshaghi Gordji, Ali Jabbari, Abasalt Bodaghi (2019)

Mathematica Bohemica

The generalized notion of weak amenability, namely ( ϕ , ψ ) -weak amenability, where ϕ , ψ are continuous homomorphisms on a Banach algebra 𝒜 , was introduced by Bodaghi, Eshaghi Gordji and Medghalchi (2009). In this paper, the ( ϕ , ψ ) -weak amenability on the measure algebra M ( G ) , the group algebra L 1 ( G ) and the Segal algebra S 1 ( G ) , where G is a locally compact group, are studied. As a typical example, the ( ϕ , ψ ) -weak amenability of a special semigroup algebra is shown as well.

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