$P$-convexity and $B$-convexity in Banach spaces
نویسندگان
چکیده
منابع مشابه
On P- and p-Convexity of Banach Spaces
and Applied Analysis 3 Lemma 2.7 Goebel-Kirk . Let X be a Banach space. For each ε ∈ ε0 X , 2 , one has the equality δX 2 − 2δX ε 1 − ε/2. Lemma 2.8 Ullán . Let X be a Banach space. For each 0 ≤ ε2 ≤ ε1 < 2 the following inequality holds: δX ε1 − δX ε2 ≤ ε1 − ε2 / 2 − ε1 . Using these lemmas we obtain: Theorem 2.9. Let X be a Banach space which satisfies δX 1 > 0, that is, ε0 X < 1. Then X is P...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1974
ISSN: 0002-9947
DOI: 10.1090/s0002-9947-1974-0333678-0