Czasopismo
Tytuł artykułu
Autorzy
Warianty tytułu
Języki publikacji
Abstrakty
We study the c₀-content of a seminormalized basic sequence (χₙ) in a Banach space, by the use of ordinal indices (taking values up to ω₁) that determine dichotomies at every ordinal stage, based on the Ramsey-type principle for every countable ordinal, obtained earlier by the author. We introduce two such indices, the c₀-index $ξ^{(χₙ)}₀$ and the semibounded completeness index $ξ^{(χₙ)}_b$, and we examine their relationship. The countable ordinal values that these indices can take are always of the form $ω^{ζ}$. These results extend, to the countable ordinal level, an earlier result by Odell, which was stated only for the limiting case of the first uncountable ordinal.
Słowa kluczowe
Kategorie tematyczne
Czasopismo
Rocznik
Tom
Numer
Strony
153-179
Opis fizyczny
Daty
wydano
2002
Twórcy
autor
- Department of Mathematics, University of Athens, Panepistimiopolis, 15784 Athens, Greece
Bibliografia
Typ dokumentu
Bibliografia
Identyfikatory
Identyfikator YADDA
bwmeta1.element.bwnjournal-article-doi-10_4064-fm172-2-4