Bernstein-type characterization of entire functions
DOI:
https://doi.org/10.15407/dopovidi2023.01.010Keywords:
Bernstein theorem, entire function, polynomial approximation, Shauder basis, transfinite diameterAbstract
Let ε be the set of all entire functions on the complex plane C. Let us consider the class XE of all complex Banach spaces X such that X ⊇ ε . For (X, ⎥⎥ ⋅ ⎥⎥)∈XE and g ∈X we write En, X (g ) = inf {⎥⎥ g − p⎥⎥: p∈Πn }, where Πn is the set of all polynomials with degree at most n. We describe all X ∈XE for which the relation lim n→∞ (En, X( g ))1/n = 0 holds if and only if g ∈ ε.
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