Invariant subspaces and weighted polynomial approximation
نویسندگان
چکیده
منابع مشابه
Analytic Continuation and Embeddings in Weighted Backward Shift Invariant Subspaces
By a famous result, functions in backward shift invariant subspaces in Hardy spaces are characterized by the fact that they admit a pseudocontinuation a.e. on T. More can be said if the spectrum of the associated inner function has holes on T. Then the functions of the invariant subspaces even extend analytically through these holes. We will discuss the situation in weighted backward shift inva...
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We prove here some polynomial approximation theorems, somewhat related to the Szasz-Mfintz theorem, but where the domain of approximation is the integers, by dualizing a gap theorem of C. l ~ Y I for periodic entire functions. In another Paper [7], we shall prove, by similar means, a completeness theorem ibr some special sets of entire functions. I t is well known (see, for example [l]) tha t i...
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ژورنال
عنوان ژورنال: Arkiv för Matematik
سال: 1973
ISSN: 0004-2080
DOI: 10.1007/bf02388514