Some Stability Theorems for Nonharmonic Fourier Series
نویسندگان
چکیده
The theory of nonharmonic Fourier series in L2(-ir,tr) is concerned with the completeness and expansion properties of sets of complex exponentials {e'x"'}. It is well known, for example, that the completeness of the set {e'x"'} ensures that of {e'^"'} whenever 2 lA„ ~~ M»l < oo. In this note we establish two results which guarantees that if {elX"'} is a Schauder basis for l}(—n, it), then [e'^"'} is also a Schauder basis whenever (jin) is "sufficiently close" to {A„}.
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تاریخ انتشار 2010