Abstract
For Favard kernels, which are used to construct polynomials of best approximation for classes of periodic differentiable functions W r, we obtain exact values of their norms as simple finite sums for odd r and lower bounds for the norms for even r. Similar results are also obtained for the norms of the adjoint Favard kernels.
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Subbotin, Y.N., Telyakovskii, S.A. On the norms of Favard Kernels. Math Notes 97, 598–604 (2015). https://doi.org/10.1134/S000143461503030X
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DOI: https://doi.org/10.1134/S000143461503030X