Some Fourier inequalities for orthogonal systems in Lorentz–Zygmund spaces

Abstract

Abstract A number of classical inequalities and convergence results related to Fourier coefficients with respect to unbounded orthogonal systems are generalized and complemented. All results are given in the case of Lorentz–Zygmund spaces.

Keywords

• Inequalities
• Fourier series
• Fourier coefficients
• Unbounded orthogonal systems
• Lorentz–Zygmund spaces