and $r>\frac1p+\frac12$, $$ \lambda_n(\widetilde W^r_p,L_q)\asymp\begin{cases}n^{-r+\frac1p-\frac12},&\frac1p+\frac1q\leqslant1,\\n^{-r+\frac12-\frac1q},&\frac1p+\frac1q>1.\end{cases} $$ This formula, together with the known results for other $(p,q)$, finishes the solution of the problem of asymptotic computation of the linear diameters for the Sobolev classes in the one-dimensional periodic case when $r>\frac1p+\frac12$. Bibliography: 28 titles.
@article{SM_1982_41_3_a2,
author = {V. E. Maiorov},
title = {On linear widths of {Sobolev} classes and chains of extremal subspaces},
journal = {Sbornik. Mathematics},
pages = {361--382},
year = {1982},
volume = {41},
number = {3},
language = {en},
url = {http://geodesic.mathdoc.fr/item/SM_1982_41_3_a2/}
}
V. E. Maiorov. On linear widths of Sobolev classes and chains of extremal subspaces. Sbornik. Mathematics, Tome 41 (1982) no. 3, pp. 361-382. http://geodesic.mathdoc.fr/item/SM_1982_41_3_a2/
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