NEIGHBORHOOD OF A CLASS OF ANALYTIC FUNCTIONS WITH NEGATIVE COEFFICIENTS DEFINED BY THE GENERALIZED RUSCHEWEY DERIVATIVES INVOLVING A GENERAL FRACTIONAL DERIVATIVE OPERATOR

By making use of the familiar concept of neighborhoods of analytic functions, we prove several inclusion relations associated with the (n, delta)-neighborhoods of various subclasses of starlike and convex functions of complex order defined by the generalized Ruscheweyh derivative involving a general fractional derivative operator. Special cases of some of these inclusion relations are shown to yield known results.