RUS  ENG
Full version
JOURNALS // Trudy Instituta Matematiki i Mekhaniki UrO RAN // Archive

Trudy Inst. Mat. i Mekh. UrO RAN, 2011 Volume 17, Number 3, Pages 71–82 (Mi timm722)

This article is cited in 1 paper

Estimates of the Lebesgue function of Fourier sums over trigonometric polynomials orthogonal with a weight not belonging to the spaces $L^r$ $(r>1)$

V. M. Badkovab

a Institute of Mathematics and Mechanics, Ural Branch of the Russian Academy of Sciences
b Ural Federal University

Abstract: A two-sided pointwise estimate is obtained for the Lebesgue function of Fourier sums with respect to trigonometric polynomials orthogonal with a $2\pi$-periodic weight that differs from the function $1/|\sin(\tau/2)|$ by some factor slowly changing at zero. The weight under consideration does not belong to the space $L^r$ for any $r>1$. A similar result for polynomials orthogonal on the interval $[-1,1]$ is obtained in the form of a corollary.

Keywords: Lebesgue function, orthogonal polynomials, periodic weight.

UDC: 517.5

Received: 30.03.2011


 English version:
Proceedings of the Steklov Institute of Mathematics (Supplement Issues), 2012, 277, suppl. 1, S21–S32

Bibliographic databases:


© Steklov Math. Inst. of RAS, 2025