Sharp approximations to the Bernoulli periodic functions by trigonometric polynomials
نویسنده
چکیده
We obtain optimal trigonometric polynomials of a given degree N that majorize, minorize and approximate in L(R/Z) the Bernoulli periodic functions. These are the periodic analogues of two works of F. Littmann ([9] and [10]) that generalize a paper of J. Vaaler ([14]). As applications we provide the corresponding Erdös-Turán-type inequalities, approximations to other periodic functions and bounds for certain Hermitian forms.
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عنوان ژورنال:
- Journal of Approximation Theory
دوره 154 شماره
صفحات -
تاریخ انتشار 2008