Characterizations of almost shrinking bases
Abstract
The material of this paper depends upon the theory of locally convex spaces, sequence spaces and Schauder bases in topological vector spaces and as such we refer to [2] (cf. also [9]), [6] and [7] respectively for several unexpalined definitions, results and terms prevalent in the sequel.However, we do recall a few definitions and terms relevant to the present paper. So, we write thorughout
for an arbitrary Hausdorff locally convex space (l.c.s.) with
denoting the topological dual of X and
representing the saturated collection of all T-continuous seminorms generating the locally convex (l.c) topology T on X.Also we write the pair of sequences
for an arbitrary Schauder basis (S.b.) for X where
and
An S.b.
for
is called shrinking if
is an S.b. for the strong dual
being the usual canonical embedding from X into(Error rendering LaTeX formula)
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DOI Code:
10.1285/i15900932v10n1p67
Full Text: PDF