The sharp bound of the third Hankel determinant for some classes of analytic functions
2
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
In the present paper, we have proved the sharp inequality $|H_{3,1}(f)|$ $\le 4$ and $|H_{3,1}(f)|\le 1$ for analytic functions $f$ with $a_n:=f^{(n)}(0)/n!,\ n\in\mathbb{N},$ such that $$\mathrm{Re}\, \frac{f(z)}{z}> \alpha,\quad z\in\mathbb{D}:=\{z \in\mathbb{C} : |z|<1\}$$ for $\alpha=0$ and $\alpha=1/2,$ respectively, where \begin{equation*} H_{3,1}(f):= \begin{vmatrix} a_1 & a_2 & a_3 \\ a_2 & a_3 & a_4 \\ a_3 & a_4 & a_5 \end{vmatrix} \end{equation*} is the third Hankel determinant.
Abstract
In the present paper, we have proved the sharp inequality $|H_{3,1}(f)|$ $\le 4$ and $|H_{3,1}(f)|\le 1$ for analytic functions $f$ with $a_n:=f^{(n)}(0)/n!,\ n\in\mathbb{N},$ such that $$\mathrm{Re}\, \frac{f(z)}{z}> \alpha,\quad z\in\mathbb{D}:=\{z \in\mathbb{C} : |z|<1\}$$ for $\alpha=0$ and $\alpha=1/2,$ respectively, where \begin{equation*} H_{3,1}(f):= \begin{vmatrix} a_1 & a_2 & a_3 \\ a_2 & a_3 & a_4 \\ a_3 & a_4 & a_5 \end{vmatrix} \end{equation*} is the third Hankel determinant.
참고문헌 (30)
- K. O. Babalola, "Inequality Theory and Applications, vol. 6", pp.1~7 (2010), Nova Science Publishers
- Deepak Bansal, "THIRD ORDER HANKEL DETERMINANT FOR CERTAIN UNIVALENT FUNCTIONS", 대한수학회지, 52(6), pp.1139~1148 (2015), 대한수학회
- C. Caratheodory, "Uber den Variabilitatsbereich der Koeffizienten von Potenzreihen, die gegebene Werte nicht annehmen", Math. Ann, 64(1), pp.95~115 (1907)
- N. E. Cho, "Some coefficient inequalities related to the Hankel determinant for strongly starlike functions of order alpha", J. Math. Inequal, 11(2), pp.429~439 (2017)
- N. E. Cho, "The bounds of some determinants for starlike functions of order alpha", Bull. Malays. Math. Sci. Soc, 41(1), pp.523~535 (2018)
- P. L. Duren, "Univalent Functions, Grundlehren der Mathematischen Wissenschaften, 259" (1983), Springer-Verlag
- M. Elin, "Linearization Models for Complex Dynamical Systems" (2010), Birkhauser Verlag
- A. W. Goodman, "Univalent Functions" (1983), Mariner
- A. Janteng, "Hankel determinant for starlike and convex functions", Int. J. Math. Anal. (Ruse), 1(13-16), pp.619~625 (2007)
- BOGUMIŁA KOWALCZYK, "THE SHARP BOUND FOR THE HANKEL DETERMINANT OF THE THIRD KIND FOR CONVEX FUNCTIONS", Bulletin of the Australian Mathematical Society, 97(03), pp.435~445 (2018), Cambridge University Press (CUP)[DOI]
- B. Kowalczyk, "The sharp bound of the Hankel determinant of the third kind for starlike functions of order 1=2", ~
- Oh Sang Kwon, "On the Fourth Coefficient of Functions in the Carathéodory Class", Computational Methods and Function Theory, 18(2), pp.307~314 (2018), Springer Nature[DOI]
- S. K. Lee, "Bounds for the second Hankel determinant of certain univalent functions", J. Inequal. Appl, 2013, pp.281~ (2013)
- R. J. Libera, "Early coefficients of the inverse of a regular convex function", Proc. Amer. Math. Soc, 85(2), pp.225~230 (1982)
- R. J. Libera, "Coefficient bounds for the inverse of a function with derivative in P", Proc. Amer. Math. Soc, 87(2), pp.251~257 (1983)
- T. H. MacGregor, "The radius of univalence of certain analytic functions", Proc. Amer. Math. Soc, 14, pp.514~520 (1963)
- A. Marx, "Untersuchungen uber schlichte Abbildungen", Math. Ann, 107(1), pp.40~67 (1933)
- S. S. Miller, "Differential Subordinations" (2000), Marcel Dekker, Inc.
- A. K. Mishra, "Second Hankel determinant for a class of analytic functions defined by fractional derivative", Int. J. Math. Math. Sci, 2008, pp.10~ (2008)
- C. Pommerenke, "Univalent Functions" (1975), Vandenhoeck & Ruprecht
- J. K. Prajapat, "Bounds on third Hankel determinant for close-to-convex functions", Acta Univ. Sapientiae Math, 7(2), pp.210~219 (2015)
- J. S. Ratti, "The radius of univalence of certain analytic functions", Math. Z, 107, pp.241~248 (1968)
- M. Raza, "Upper bound of the third Hankel determinant for a class of analytic functions related with lemniscate of Bernoulli", J. Inequal. Appl, 2013, pp.412~ (2013)
- M. I. S. Robertson, "On the theory of univalent functions", Ann. of Math. (2), 37(2), pp.374~408 (1936)
- G. Shanmugam, "Third Hankel determinant for -starlike functions", Gulf J. Math, 2(2), pp.107~113 (2014)
- D. Shoikhet, "Rigidity and parametric embedding of semi-complete vector fields on the unit disk", Milan J. Math, 84(1), pp.159~202 (2016)
- E. Strohhacker, "Beitrage zur Theorie der schlichten Funktionen", Math. Z, 37(1), pp.356~380 (1933)
- E. Study, "Vorlesungen uber ausgewahlte Gegenstande der Geometrie, Zweites Heft;Konforme Abbildung Einfach-Zusammenhangender Bereiche" (1913), Druck und Verlag von B.G. Teubner
- T. V. Sudharsan, "Third Hankel determinant for a subclass of analytic functions", Malaya J. Math, 2(4), pp.438~444 (2014)
- P. Zaprawa, "Third Hankel determinants for subclasses of univalent functions", Mediterr. J. Math, 14(1), pp.10~ (2017)
