Coefficient estimates for subclass of analytic and bi-univalent functions defined by differential operator

In this paper, we introduce and investigate a subclass $N_{\Sigma}^{h, p}(n, \delta, \mu, \lambda) $ of analytic and bi-univalent functions in the open unit disk $\mathbb{U}$. Upper bounds for the second and third coefficients of functions in this subclass are founded. Our results, which are presented in this paper, generalize and improve those in related works of several earlier authors.