Fekete–Szegő inequality
In mathematics, the Fekete–Szegő inequality is an inequality for the coefficients of univalent analytic functions found by, related to the Bieberbach conjecture. Finding similar estimates for other classes of functions is called the Fekete–Szegő problem.
The Fekete–Szegő inequality states that if
is a univalent analytic function on the unit disk and 0 ≤ λ < 1, then
