Approximative characteristics of the Nikol’skii – Besov classes of functions $S_{1, θ}^r B(\mathbb{R}^d)$

• Дата: 2026
• Автори: Radchenko, O. Ya., Yanchenko, S. Ya., Радченко, О. Я., Янченко, С. Я.
• Формат: Стаття
• Мова: Українська
• Опубліковано: Institute of Mathematics, NAS of Ukraine 2026
• Онлайн доступ: https://umj.imath.kiev.ua/index.php/umj/article/view/1523
• Назва журналу: Ukrains’kyi Matematychnyi Zhurnal

UDC 517.51 We establish the exact-order estimates for the approximation of the classes $S^{\boldsymbol{r}}_{1,\theta}B \left(\mathbb{R}^d\right)$ by entire functions of exponential type with supports of their Fourier transforms lying in a step hyperbolic cross. The error of approximation is estima...