Sharp inverse logarithmic coefficient bounds for starlike functions associated with cosine function
DOI:
https://doi.org/10.24193/subbmath.2026.1.06Keywords:
Starlike functions, inverse logarithmic coefficients, Hankel determinant, Toeplitz determinantAbstract
Let \mathcal{S}_{cos}^{\ast } be the subclass of starlike functions f associated with cosine function defined by \left( zf^{\prime
}(z)/f(z)\right) \prec \cos (z). In this paper, we obtain the sharp coefficient bounds and Hankel determinants of second order for the inverse logarithmic function for this class. We also present the best possible bounds of second order Toeplitz determinant for the functions in the same class.
Mathematics Subject Classification (2010): 30C45, 30C50.
Received 03 August 2025; Accepted 01 December 2025.
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