IDEAS home Printed from https://ideas.repec.org/a/gam/jmathe/v10y2022i20p3862-d945884.html
   My bibliography  Save this article

Sharp Coefficient Problems of Functions with Bounded Turnings Subordinated by Sigmoid Function

Author

Listed:
  • Muhammad Arif

    (Faculty of Physical and Numerical Sciences, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan)

  • Safa Marwa

    (Faculty of Physical and Numerical Sciences, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan)

  • Qin Xin

    (Faculty of Science and Technology, University of the Faroe Islands, Vestarabryggja 15, FO 100 Torshavn, Faroe Islands, Denmark)

  • Fairouz Tchier

    (Department of Mathematics, College of Science, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia)

  • Muhammad Ayaz

    (Faculty of Physical and Numerical Sciences, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan)

  • Sarfraz Nawaz Malik

    (Department of Mathematics, COMSATS University Islamabad, Wah Campus, Wah Cantt 47040, Pakistan)

Abstract

This study deals with analytic functions with bounded turnings, defined in the disk O d = z : z < 1 . These functions are subordinated by sigmoid function 2 1 + e − z and their class is denoted by BT Sg . Sharp coefficient inequalities, including the third Hankel determinant for class BT Sg , were investigated here. The same was also included for the logarithmic coefficients related to functions of the class BT Sg .

Suggested Citation

  • Muhammad Arif & Safa Marwa & Qin Xin & Fairouz Tchier & Muhammad Ayaz & Sarfraz Nawaz Malik, 2022. "Sharp Coefficient Problems of Functions with Bounded Turnings Subordinated by Sigmoid Function," Mathematics, MDPI, vol. 10(20), pages 1-24, October.
    • Handle: RePEc:gam:jmathe:v:10:y:2022:i:20:p:3862-:d:945884
    as

    Download full text from publisher

    File URL: https://www.mdpi.com/2227-7390/10/20/3862/pdf
    Download Restriction: no
    File URL: https://www.mdpi.com/2227-7390/10/20/3862/
    Download Restriction: no
    ---><---

    References listed on IDEAS

    as
    1. Lei Shi & Muhammad Arif & Ayesha Rafiq & Muhammad Abbas & Javed Iqbal, 2022. "Sharp Bounds of Hankel Determinant on Logarithmic Coefficients for Functions of Bounded Turning Associated with Petal-Shaped Domain," Mathematics, MDPI, vol. 10(11), pages 1-19, June.
    2. Hari M. Srivastava & Qazi Zahoor Ahmad & Maslina Darus & Nazar Khan & Bilal Khan & Naveed Zaman & Hasrat Hussain Shah, 2019. "Upper Bound of the Third Hankel Determinant for a Subclass of Close-to-Convex Functions Associated with the Lemniscate of Bernoulli," Mathematics, MDPI, vol. 7(9), pages 1-10, September.
    3. Afis Saliu & Khalida Inayat Noor & Saqib Hussain & Maslina Darus & Hijaz Ahmad, 2020. "On Quantum Differential Subordination Related with Certain Family of Analytic Functions," Journal of Mathematics, Hindawi, vol. 2020, pages 1-13, November.
    4. Lei Shi & Muhammad Arif & Mohsan Raza & Muhammad Abbas, 2022. "Hankel Determinant Containing Logarithmic Coefficients for Bounded Turning Functions Connected to a Three-Leaf-Shaped Domain," Mathematics, MDPI, vol. 10(16), pages 1-10, August.
    5. Gangadharan Murugusundaramoorthy & Teodor Bulboacă, 2020. "Hankel Determinants for New Subclasses of Analytic Functions Related to a Shell Shaped Region," Mathematics, MDPI, vol. 8(6), pages 1-14, June.
    6. Isra Al-Shbeil & Afis Saliu & Adriana Cătaş & Sarfraz Nawaz Malik & Semiu Oladipupo Oladejo, 2022. "Some Geometrical Results Associated with Secant Hyperbolic Functions," Mathematics, MDPI, vol. 10(15), pages 1-13, July.
    7. Abdullah Alotaibi & Muhammad Arif & Mohammed A. Alghamdi & Shehzad Hussain, 2020. "Starlikness Associated with Cosine Hyperbolic Function," Mathematics, MDPI, vol. 8(7), pages 1-16, July.
    8. Hari M. Srivastava & Qazi Zahoor Ahmad & Nasir Khan & Nazar Khan & Bilal Khan, 2019. "Hankel and Toeplitz Determinants for a Subclass of q -Starlike Functions Associated with a General Conic Domain," Mathematics, MDPI, vol. 7(2), pages 1-15, February.
    Full references (including those not matched with items on IDEAS)

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Isra Al-Shbeil & Muhammad Imran Faisal & Muhammad Arif & Muhammad Abbas & Reem K. Alhefthi, 2023. "Investigation of the Hankel Determinant Sharp Bounds for a Specific Analytic Function Linked to a Cardioid-Shaped Domain," Mathematics, MDPI, vol. 11(17), pages 1-22, August.
    2. Nazar Khan & Shahid Khan & Qin Xin & Fairouz Tchier & Sarfraz Nawaz Malik & Umer Javed, 2023. "Some Applications of Analytic Functions Associated with q -Fractional Operator," Mathematics, MDPI, vol. 11(4), pages 1-17, February.
    3. Rabha W. Ibrahim & Rafida M. Elobaid & Suzan J. Obaiys, 2020. "A Class of Quantum Briot–Bouquet Differential Equations with Complex Coefficients," Mathematics, MDPI, vol. 8(5), pages 1-13, May.
    4. Huo Tang & Ihtesham Gul & Saqib Hussain & Saima Noor, 2023. "Bounds for Toeplitz Determinants and Related Inequalities for a New Subclass of Analytic Functions," Mathematics, MDPI, vol. 11(18), pages 1-15, September.
    5. Hai-Yan Zhang & Rekha Srivastava & Huo Tang, 2019. "Third-Order Hankel and Toeplitz Determinants for Starlike Functions Connected with the Sine Function," Mathematics, MDPI, vol. 7(5), pages 1-10, May.
    6. Shahid Khan & Saqib Hussain & Muhammad Naeem & Maslina Darus & Akhter Rasheed, 2021. "A Subclass of q -Starlike Functions Defined by Using a Symmetric q -Derivative Operator and Related with Generalized Symmetric Conic Domains," Mathematics, MDPI, vol. 9(9), pages 1-12, April.
    7. Miraj Ul-Haq & Mohsan Raza & Muhammad Arif & Qaiser Khan & Huo Tang, 2019. "q-Analogue of Differential Subordinations," Mathematics, MDPI, vol. 7(8), pages 1-16, August.
    8. Saeed Islam & Muhammad Ghaffar Khan & Bakhtiar Ahmad & Muhammad Arif & Ronnason Chinram, 2020. "Q -Extension of Starlike Functions Subordinated with a Trigonometric Sine Function," Mathematics, MDPI, vol. 8(10), pages 1-14, October.
    9. Hari M. Srivastava & Nazar Khan & Shahid Khan & Qazi Zahoor Ahmad & Bilal Khan, 2021. "A Class of k -Symmetric Harmonic Functions Involving a Certain q -Derivative Operator," Mathematics, MDPI, vol. 9(15), pages 1-14, July.
    10. Georgia Irina Oros, 2022. "Geometrical Theory of Analytic Functions," Mathematics, MDPI, vol. 10(18), pages 1-4, September.
    11. Hari Mohan Srivastava & Nazar Khan & Maslina Darus & Shahid Khan & Qazi Zahoor Ahmad & Saqib Hussain, 2020. "Fekete-Szegö Type Problems and Their Applications for a Subclass of q -Starlike Functions with Respect to Symmetrical Points," Mathematics, MDPI, vol. 8(5), pages 1-18, May.
    12. Yue-Juan Sun & Muhammad Arif & Lei Shi & Muhammad Imran Faisal, 2023. "Some Further Coefficient Bounds on a New Subclass of Analytic Functions," Mathematics, MDPI, vol. 11(12), pages 1-14, June.
    13. Lei Shi & Muhammad Arif & Mohsan Raza & Muhammad Abbas, 2022. "Hankel Determinant Containing Logarithmic Coefficients for Bounded Turning Functions Connected to a Three-Leaf-Shaped Domain," Mathematics, MDPI, vol. 10(16), pages 1-10, August.
    14. Lei Shi & Muhammad Arif & Ayesha Rafiq & Muhammad Abbas & Javed Iqbal, 2022. "Sharp Bounds of Hankel Determinant on Logarithmic Coefficients for Functions of Bounded Turning Associated with Petal-Shaped Domain," Mathematics, MDPI, vol. 10(11), pages 1-19, June.
    15. Qaiser Khan & Muhammad Arif & Mohsan Raza & Gautam Srivastava & Huo Tang & Shafiq ur Rehman, 2019. "Some Applications of a New Integral Operator in q -Analog for Multivalent Functions," Mathematics, MDPI, vol. 7(12), pages 1-13, December.
    16. Lei Shi & Izaz Ali & Muhammad Arif & Nak Eun Cho & Shehzad Hussain & Hassan Khan, 2019. "A Study of Third Hankel Determinant Problem for Certain Subfamilies of Analytic Functions Involving Cardioid Domain," Mathematics, MDPI, vol. 7(5), pages 1-15, May.
    17. Lei Shi & Qaiser Khan & Gautam Srivastava & Jin-Lin Liu & Muhammad Arif, 2019. "A Study of Multivalent q -starlike Functions Connected with Circular Domain," Mathematics, MDPI, vol. 7(8), pages 1-12, July.
    18. Isra Al-Shbeil & Afis Saliu & Adriana Cătaş & Sarfraz Nawaz Malik & Semiu Oladipupo Oladejo, 2022. "Some Geometrical Results Associated with Secant Hyperbolic Functions," Mathematics, MDPI, vol. 10(15), pages 1-13, July.
    19. Bilal Khan & Zhi-Guo Liu & Hari M. Srivastava & Nazar Khan & Maslina Darus & Muhammad Tahir, 2020. "A Study of Some Families of Multivalent q -Starlike Functions Involving Higher-Order q -Derivatives," Mathematics, MDPI, vol. 8(9), pages 1-12, September.
    20. Loriana Andrei & Vasile-Aurel Caus, 2024. "Subordinations Results on a q -Derivative Differential Operator," Mathematics, MDPI, vol. 12(2), pages 1-20, January.

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:gam:jmathe:v:10:y:2022:i:20:p:3862-:d:945884. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: MDPI Indexing Manager (email available below). General contact details of provider: https://www.mdpi.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.