Best mean square approximations by entire functions of finite degree on a straight line and exact values of mean widths of functional classes

• Datum: 2010
• Hauptverfasser: Vakarchuk, S. B., Doronin, V. G., Вакарчук, С. Б., Доронин, В. Г.
• Format: Artikel
• Sprache: Russisch; Englisch
• Veröffentlicht: Institute of Mathematics, NAS of Ukraine 2010
• Online Zugang: https://umj.imath.kiev.ua/index.php/umj/article/view/2935
• Назва журналу: Ukrains’kyi Matematychnyi Zhurnal

We obtain exact Jackson-type inequalities in the case of the best mean square approximation by entire functions of finite degree $≤ σ$ on a straight line. For classes of functions defined via majorants of averaged smoothness characteristics $Ω_1(f, t ),\; t > 0$, we determine the exact values...