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Lebesgue-type inequalities for the de la Vallée-poussin sums on sets of entire functions

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Ukrainian Mathematical Journal Aims and scope

For functions from the sets C ψ β L s , 1 ≤ s ≤ ∞, where ψ(k) > 0 and \( {\lim_{{k\to \infty }}}\frac{{\psi \left( {k+1} \right)}}{{\psi (k)}} \), we obtain asymptotically sharp estimates for the norms of deviations of the de la Vallée-Poussin sums in the uniform metric represented in terms of the best approximations of the (ψ, β) -derivatives of functions of this kind by trigonometric polynomials in the metrics of the spaces L s . It is shown that the obtained estimates are sharp on some important functional subsets.

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References

  1. A P. Musienko and A. S. Serdyuk, “Lebesgue-type inequalities for the de la Vallée-Poussin sums on sets of analytic functions,” Ukr. Mat. Zh., 65, No. 4, 522–537 (2013).

    Article  MathSciNet  Google Scholar 

  2. A. I. Stepanets, Methods of Approximation Theory [in Russian], Vol. 1, Institute of Mathematics, Ukrainian National Academy of Sciences, Kiev (2002).

  3. L. P. Falaleev, “On the approximation of functions by generalized Abel–Poisson operators,” Sib. Mat. Zh., 42, No. 4, 926–936 (2001).

    Article  MathSciNet  MATH  Google Scholar 

  4. V. I. Rukasov and S. O. Chaichenko, “Approximation of analytic periodic functions by de la Vallée-Poussin sums,” Ukr. Mat. Zh., 54, No. 12, 1653–1668 (2002); English translation: Ukr. Math. J., 54, No. 12, 2006–2024 (2002).

    Article  MathSciNet  MATH  Google Scholar 

  5. V. I. Rukasov, “Approximation of the classes of analytic functions by de la Vallée-Poussin sums,” Ukr. Mat. Zh., 55, No. 6, 806–816 (2003); English translation: Ukr. Math. J., 55, No. 6, 974–986 (2003).

    Article  MathSciNet  MATH  Google Scholar 

  6. A. S. Serdyuk, “Approximation of Poisson integrals by de la Vallée Poussin sums,” Ukr. Mat. Zh., 56, No. 1, 97–107 (2004); English translation: Ukr. Math. J., 56, No. 1, 122–134 (2004).

    Article  MathSciNet  MATH  Google Scholar 

  7. A. S. Serdyuk and E. Yu. Ovsii, “Approximation on the classes of entire functions by de la Vallée-Poussin sums,” in: Approximation Theory of Functions and Related Problems, Collection of Works, Institute of Mathematics, Ukrainian National Academy of Sciences [in Ukrainian], 5, No. 1, 334–351 (2008).

  8. A. S. Serdyuk, “Approximation of Poisson integrals by de la Vallée-Poussin sums in uniform and integral metrics,” Ukr. Mat. Zh., 62, No. 12, 1672–1686 (2010); English translation: Ukr. Math. J., 62, No. 12, 1941–1957 (2010).

    MATH  Google Scholar 

  9. A. S. Serdyuk and A. P. Musienko, “Lebesgue-type inequalities for the de la Vallée-Poussin sums in the approximation of Poisson integrals,” in: Approximation Theory of Functions and Related Problems, Collection of Works, Institute of Mathematics, Ukrainian National Academy of Sciences [in Ukrainian], 7, No. 1 (2010), pp. 298–316.

  10. A. S. Serdyuk and E. Yu. Ovsii, “Uniform approximation of Poisson integrals of functions from the class H ω by de la Vallée Poussin sums,” Anal. Math., 38, No. 4, 305–325 (2012).

    Article  MathSciNet  MATH  Google Scholar 

  11. A. S. Serdyuk, E. Yu. Ovsii, and A. P. Musienko, “Approximation of classes of analytic functions by de la Vallée Poussin sums in uniform metric,” Rend. Mat., 32, 1–15 (2012).

    MathSciNet  MATH  Google Scholar 

  12. A. I. Stepanets, V. I. Rukasov, and S. O. Chaichenko, Approximation by de la Vallée-Poussin Sums [in Russian], Institute of Mathematics, Ukrainian National Academy of Sciences, Kiev (2007).

  13. A. I. Stepanets, Methods of Approximation Theory [in Russian], Vol. 2, Institute of Mathematics, Ukrainian National Academy of Sciences, Kiev (2002).

  14. N. P. Korneichuk, Exact Constants in Approximation Theory [in Russian], Nauka, Moscow (1987).

    Google Scholar 

  15. S. A. Telyakovskii, “Approximation of functions of higher smoothness by Fourier sums,” Ukr. Mat. Zh., 41, No. 4, 510–518 (1989); English translation: Ukr. Math. J., 41, No. 4, 444–451 (1989).

    Article  MathSciNet  Google Scholar 

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Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 65, No. 5, pp. 642–653, May, 2013.

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Musienko, A.P., Serdyuk, A.S. Lebesgue-type inequalities for the de la Vallée-poussin sums on sets of entire functions. Ukr Math J 65, 709–722 (2013). https://doi.org/10.1007/s11253-013-0808-4

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  • DOI: https://doi.org/10.1007/s11253-013-0808-4

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