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Subject: Analytic functionWoS Q: Q1

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Now showing 1 - 4 of 4
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    Citation - WoS: 1
    Citation - Scopus: 1
    On the q-moment Determinacy of Probability Distributions
    (Malaysian Mathematical Sciences Soc, 2020) Ostrovska, Sofiya; Turan, Mehmet
    Given 0
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    Citation - WoS: 5
    Citation - Scopus: 5
    Analytical Properties of the Lupas q-transform
    (Academic Press inc Elsevier Science, 2012) Ostrovska, Sofiya
    The Lupas q-transform emerges in the study of the limit q-Lupas operator. The latter comes out naturally as a limit for a sequence of the Lupas q-analogues of the Bernstein operator. Given q is an element of (0, 1), f is an element of C left perpendicular0, 1right perpendicular, the q-Lupas transform off is defined by (Lambda(q)f) (z) := 1/(-z; q)(infinity) . Sigma(infinity)(k=0) f(1 - q(k))q(k(k -1)/2)/(q; q)(k)z(k). The transform is closely related to both the q-deformed Poisson probability distribution, which is used widely in the q-boson operator calculus, and to Valiron's method of summation for divergent series. In general, Lambda(q)f is a meromorphic function whose poles are contained in the set J(q) := {-q(-j)}(j=0)(infinity). In this paper, we study the connection between the behaviour of f on leftperpendicular0, 1right perpendicular and the decay of Lambda(q)f as z -> infinity. (C) 2012 Elsevier Inc. All rights reserved.
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    Citation - WoS: 2
    Citation - Scopus: 2
    On the Analyticity of Functions Approximated by Their q-bernstein Polynomials When q > 1
    (Elsevier Science inc, 2010) Ostrovskii, Iossif; Ostrovska, Sofiya
    Since in the case q > 1 the q-Bernstein polynomials B-n,B-q are not positive linear operators on C[0, 1], the investigation of their convergence properties for q > 1 turns out to be much harder than the one for 0 < q < 1. What is more, the fast increase of the norms parallel to B-n,B-q parallel to as n -> infinity, along with the sign oscillations of the q-Bernstein basic polynomials when q > 1, create a serious obstacle for the numerical experiments with the q-Bernstein polynomials. Despite the intensive research conducted in the area lately, the class of functions which are uniformly approximated by their q-Bernstein polynomials on [0, 1] is yet to be described. In this paper, we prove that if f : [0, 1] -> C is analytic at 0 and can be uniformly approximated by its q-Bernstein polynomials (q > 1) on [0, 1], then f admits an analytic continuation from [0, 1] into {z: vertical bar z vertical bar < 1}. (C) 2010 Elsevier Inc. All rights reserved.
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    Citation - WoS: 8
    Citation - Scopus: 8
    On the Lupas q-transform
    (Pergamon-elsevier Science Ltd, 2011) Ostrovska, Sofiya
    The Lupas q-transform emerges in the study of the limit q-Lupas operator. The latter comes out naturally as a limit for a sequence of the Lupas q-analogues of the Bernstein operator. Lately, it has been studied by several authors from different perspectives in mathematical analysis and approximation theory. This operator is closely related to the q-deformed Poisson probability distribution, which is used widely in the q-boson operator calculus. (Lambda(q)f)(z) := 1/(-z; q)(infinity) . Sigma(infinity)(k=0) f(1 - q(k))q(k(k-1)/2)/(q; q)(k) z(k). In this paper, we study some analytic properties of (Lambda(q)f)(z). In particular, we examine the conditions under which Lambda(q)f can either be an entire function, or a rational one. (C) 2010 Elsevier Ltd. All rights reserved.