On convergence of Bernstein--Kantorovich operators sequence in variable exponent Lebesgue spaces
Izvestiya of Saratov University. Mathematics. Mechanics. Informatics, Tome 16 (2016) no. 3, pp. 322-330.

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Let $E=[0,1]$ and let a function $p(x)\ge1$ be measurable and essentially bounded on $E$. We denote by $L^{p(x)}(E)$ the set of measurable function $f$ on $E$ for which $\int_{E}|f(x)|^{p(x)}dx\infty$. The convergence of a sequence of operators of Bernstein–Kantorovich $\{K_n(f,x)\}_{n=1}^\infty$ to the function $f$ in Lebesgue spaces with variable exponent $L^{p(x)}(E)$ is studied. The conditions on the variable exponent at which this sequence is uniformly bounded in these spaces are obtained and, as a corollary, it is shown that if $n\to\infty$ then $K_n(f,x)$ converges to function $f$ in the metric of space $L^{p(x)}(E)$ defined by the norm $\|f\|_{p(\cdot)}=\|f\|_{p(\cdot)}(E)=\inf\left\{\alpha>0:\quad\int\limits_E\left|\frac{f(x)}\alpha\right|^{p(x)}dx\le1\right\}$.
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T. N. Shakh-Emirov. On convergence of Bernstein--Kantorovich operators sequence in variable exponent Lebesgue spaces. Izvestiya of Saratov University. Mathematics. Mechanics. Informatics, Tome 16 (2016) no. 3, pp. 322-330. http://geodesic.mathdoc.fr/item/ISU_2016_16_3_a9/

[1] Kantorovich L. V., “Sur certains developpements suivant les polyn$\hat{o}$mes de la forme de S. Bernstein. I; II”, C. R. Acad. Sci. URSS, 1930, 563–568; 595–600

[2] Lorentz G. G., Bernstein Polynomials, Univ. Toronto Press, Toronto, 1953, 130 pp. | MR | Zbl

[3] Sharapudinov I. I., “Topology of the space $L^{p(t)}([0,1])$”, Math. Notes, 26:4 (1979), 796–806 | DOI | MR | Zbl

[4] Sharapudinov I. I., Some aspects of approximation theory in variable Lebesgue spaces, YuMI VNTs RAN i RSO-A, Vladikavkaz, 2012, 270 pp. (in Russian)

[5] Natanson I. P., Constructive theory of functions, GITTL, M.–L., 1949, 688 pp. (in Russian)

[6] Borovkov A. A., Probability Theory, Textbook for High Schools, Nauka, M., 1986, 432 pp. (in Russian)

[7] Vulih B. Z., Introduction to functional analisys, Nauka, M., 1967, 416 pp. (in Russian)