on sufficiency and duality for nonsmooth multiobjective programming problems involving generalized v–r-invex functions

in this paper, a class of nonsmooth multiobjective programming problems with inequality constraints is considered. we introduce the concepts of v–r-pseudo-invex, strictly v–r-pseudo-invex and v–r-quasi-invex functions, in which the involved functions are locally lipschitz. based upon these generalized v–r-invex functions, sufficient optimality conditions for a feasible point to be an efficient or a weakly efficient solution are derived. appropriate duality theorems are proved for a mond–weir-type dual program of a nonsmooth multiobjective programming under the aforesaid functions.