General coefficient bounds of $ q $-close-to convex functions associated with a vertical strip domain

Tuğba Yavuz; Tuğba Yavuz

doi:10.3934/math.20261001

AIMS Mathematics

2026, Volume 11, Issue 8: 24913-24927. doi: 10.3934/math.20261001

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General coefficient bounds of $ q $-close-to convex functions associated with a vertical strip domain

Tuğba Yavuz ^,

Department of Mathematics, Istanbul Beykent University, Faculty of Arts and Sciences, Istanbul 34500, Türkiye

Received: 26 March 2026 Revised: 21 July 2026 Accepted: 29 July 2026 Published: 13 August 2026
MSC : 30C45, 05A30

In the present study, we define a new subclass of $ q $-close-to-convex functions associated with a vertical strip domain within the framework of $ q $- calculus. For functions belonging to this class, sharp upper bounds for the initial Taylor Maclaurin coefficients are established. The analysis is carried out by employing the principle of subordination together with properties of functions with a positive real part. Several coefficient inequalities are obtained, thereby extending and refining the known results for classical close-to-convex functions and their $ q $-analogues.
- analytic functions,
- $ q $-calculus,
- close-to-convex functions,
- coefficient bounds,
- principle of subordination
Citation: Tuğba Yavuz. General coefficient bounds of $ q $-close-to convex functions associated with a vertical strip domain[J]. AIMS Mathematics, 2026, 11(8): 24913-24927. doi: 10.3934/math.20261001

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Abstract

In the present study, we define a new subclass of $ q $-close-to-convex functions associated with a vertical strip domain within the framework of $ q $- calculus. For functions belonging to this class, sharp upper bounds for the initial Taylor Maclaurin coefficients are established. The analysis is carried out by employing the principle of subordination together with properties of functions with a positive real part. Several coefficient inequalities are obtained, thereby extending and refining the known results for classical close-to-convex functions and their $ q $-analogues.

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