The Isometric Path Number of a Graph

David C. Fisher1, Shannon L. Fitzpatrick2
1 University of Colorado Denver, Colorado 80217-3364
2University of Prince Edward Island Charlottetown, Prince Edward Island C1A 4P3

Abstract

An isometric path is merely any shortest path between two vertices. Inspired by the game of `Cops and Robber’ and a result by Aigner \(\&\) Fromme [1], we are interested in determining the minimum number of isometric paths required to cover the vertices of a graph. We find a lower bound on this number in terms of the diameter of a graph and find the exact number for trees and grid graphs.