Approximation of classes of differentiable functions
Matematičeskie zametki, Tome 9 (1971) no. 2, pp. 105-112
Voir la notice de l'article provenant de la source Math-Net.Ru
Conditions are derived under which
$$
F=\sup_{||f^{(k)}||_{L_p(S)}\leqslant1}\,\inf_{||\varphi^{(l)}||_{L_r(S)}\leqslant n}||f-\varphi||_{L_p(S)}
$$
is finite or infinite. The value of $F$ is calculated for certain special cases.
@article{MZM_1971_9_2_a0,
author = {V. V. Arestov and V. N. Gabushin},
title = {Approximation of classes of differentiable functions},
journal = {Matemati\v{c}eskie zametki},
pages = {105--112},
publisher = {mathdoc},
volume = {9},
number = {2},
year = {1971},
language = {ru},
url = {http://geodesic.mathdoc.fr/item/MZM_1971_9_2_a0/}
}
V. V. Arestov; V. N. Gabushin. Approximation of classes of differentiable functions. Matematičeskie zametki, Tome 9 (1971) no. 2, pp. 105-112. http://geodesic.mathdoc.fr/item/MZM_1971_9_2_a0/