A forgotten theorem of Pełczyński: $(\lambda +)$-injective spaces need not be $\lambda $-injective—the case $\lambda \in (1,2]$
نویسندگان
چکیده
Isbell and Semadeni [Trans. Amer. Math. Soc. 107 (1963)] proved that every infinite-dimensional $1$-injective Banach space contains a hyperplane is $(2+\varepsilon )$-injective for $\varepsilon \gt 0$, yet not $2$-injective, rem
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ژورنال
عنوان ژورنال: Studia Mathematica
سال: 2023
ISSN: ['0039-3223', '1730-6337']
DOI: https://doi.org/10.4064/sm220119-25-6