Projections of normed linear spaces with closed subspaces of finite codimension as kernels
نویسندگان
چکیده
It follows from [1] and [7] that any closed n-codimensional subspace (n ≥ 1 integer) of a real Banach space X is the kernel of a projection X → X, of norm less than f(n) + ε (ε > 0 arbitrary), where f(n) = 2 + (n − 1) √ n + 2 n + 1 . We have f(n) < √ n for n > 1, and f(n) = √ n − 1 √ n + O (
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عنوان ژورنال:
- Periodica Mathematica Hungarica
دوره 52 شماره
صفحات -
تاریخ انتشار 2006