Erratum to: Sharp Constant in Jackson’s Inequality with Modulus of Smoothness for Uniform Approximations of Periodic Functions

Resumo

My paper contains an error. Namely, inequality (9) does not hold. For example, for k = 2,

I do not know whether the error in the argument can be corrected and whether the main result of the paper is valid.

I wish to express gratitude to O. L. Vinogradov for pointing out the error.