Product distance matrix of a graph and squared distance matrix of a tree

Abstract

Let G be a strongly connected, weighted directed graph. We define a product distance ?(i,j) for pairs i,j of vertices and form the corresponding product distance matrix. We obtain a formula for the determinant and the inverse of the product distance matrix. The edge orientation matrix of a directed tree is defined and a formula for its determinant and its inverse, when it exists, is obtained. A formula for the determinant of the (entry-wise) squared distance matrix of a tree is proved.