Periodic points of mappings contracting total pairwise distances
摘要
We consider a new type of mappings in metric spaces termed mappings contracting the total pairwise distances between n points. It is shown that these mappings are continuous. A theorem on the existence of periodic points for these mappings is proved and the classical Banach fixed-point theorem is obtained like a simple corollary as well as the fixed-point theorem for mappings contracting perimeters of triangles. Examples of mappings contracting the total pairwise distances between n points and having different properties are constructed.