Row Convergence Theorems for Vector-Valued Padé Approximants

Convergence of Multipoint Padé-type Approximants

Let µ be a finite positive Borel measure whose support is a compact subset K of the real line and let I be the convex hull of K. Let r denote a rational function with real coefficients whose poles lie in C \ I and r(∞) = 0. We consider multipoint rational interpolants of the function f (z) = dµ(x) z − x + r(z), where some poles are fixed and others are left free. We show that if the interpolati...

Shanks' convergence acceleration transform, Padé approximants and partitions

On the Vector - Valued Pad E Approximants

In a recent work, thanks to the use of Cliiord algebras and designants, we have shown that Wynn's vector "-algorithm can be written as a ratio of two designants. The present work, according to these new results, has the aim of 1. Finding easily and diierently the results of some authors in this scope, particularly those of Wynn, D.E. Roberts and P.R. Graves-Morris. 2. Computing explicitly the e...

Wiener Tauberian Theorems for Vector - Valued Functions

Different versions of Wiener’s Tauberian theorem are discussed for the generalized group algebra LI(G,A) (of integrable functions on a locally compact abelian group G taking values in a commutative semisimple regular Banach algebra A) using A-valued Fourier transforms. A weak form of Wiener’s Tauberian property is introduced and it is proved that LI(G,A) is weakly Tauberian if and only if A is....

Multidimensional Tauberian Theorems for Vector-valued Distributions

We prove several Tauberian theorems for regularizing transforms of vector-valued distributions. The regularizing transform of f is given by the integral transform M φ(x, y) = (f ∗ φy)(x), (x, y) ∈ R n × R+, with kernel φy(t) = yφ(t/y). We apply our results to the analysis of asymptotic stability for a class of Cauchy problems, Tauberian theorems for the Laplace transform, the comparison of quas...