GENERALIZED SEQUENCES FOR A SUBFAMILY OF UNIVALENT-FUNCTIONS

[摘要] Functions f(z) = z + ... that are analytic in the unit disk and satisfy there the inequality Re(f'(z)+zf''(z))>0 are known to be univalent. We investigate associated functions f(Z) = z + SIGMA(k)infinity = 2 a(n(k))z(n(k)) formed by choosing subsequences {n(k)} of {n}. We determine the largest disk Absolute value of z < r0 in which we are guaranteed that f is univalent and close-to-convex. (C) 1994 Academic Press, Inc.

[发布日期] 1994-04-15