Let T be the class of functions \( f(z)=z+\sum_{n=2}^{\infty }{c}_n{z}^n \) regular and typically real in the disk |z| < 1. Sharp estimates for the derivative f ′(r)(0 < r < 1) in terms of the value c3 and sharp estimates for the coefficient c3 in terms of f′(r) are obtained.
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M. S. Robertson, “On the coefficients of a typically-real function,” Bull. Amer. Math. Soc., 41, No. 8, 565–572 (1935).
G. M. Goluzin, “On typically real functions,” Mat. Sb., 27 (69), No. 2, 201–218 (1950).
J. A. Jenkins, “Some problems for typically real functions,” Canad. J. Math., 13, No. 2, 427–431 (1961).
E. G. Goluzina, “Some sharp estimates for typically real functions,” Zap. Nauchn. Semin. POMI, 428, 81–88 (2014).
E. G. Goluzina, “Sharp estimates of the first coefficients for a class of typically real functions,” Zap. Nauchn. Semin. POMI, 439, 38–46 (2015).
Yu. E. Alenitsyn, “On the ranges of systems of coefficients of functions representable by a sum of Stieltjes integrals,” Vestn. Leningr. Gos. Univ., Ser. Mat., Mekh., Astr., Vyp. 2, No. 7, 25–41 (1962).
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Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 453, 2016, pp. 15–21.
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Goluzina, E.G. On the Mutual Change of Values of the Derivative and Third Coefficient in a Class of Regular Functions. J Math Sci 224, 821–825 (2017). https://doi.org/10.1007/s10958-017-3452-y
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DOI: https://doi.org/10.1007/s10958-017-3452-y