Sharp Jackson and Bernstein inequalities for N -term approximation in sequence spaces with applications
نویسندگان
چکیده
We study N-term approximation for general families of sequence spaces, establishing sharp versions of Jackson and Bernstein inequalities. The sequence spaces used are adapted to provide characterizations of Triebel-Lizorkin and Besov spaces by means of wavelet-like systems using general dilation matrices, and thus they include spaces of anisotropic smoothness. As an application we characterize the N-term approximation spaces when the error is measured in the first of the spaces mentioned above.
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