Geodesic
On the Norms of Favard Kernels
Matematičeskie zametki, Tome 97 (2015) no. 4, pp. 583-590.

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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.
Mots-clés : Favard kernel, Favard sum
Keywords: polynomial of best approximation, function class $W^r$, Kolmogorov width. 
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Yu. N. Subbotin; S. A. Telyakovskii. On the Norms of Favard Kernels. Matematičeskie zametki, Tome 97 (2015) no. 4, pp. 583-590. http://geodesic.mathdoc.fr/item/MZM_2015_97_4_a7/

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