The Structure of Minimally 1-Tough Graphs with Small Independence Number
摘要
A graph G is minimally t-tough if the toughness of G is t and the deletion of any edge from G decreases its toughness, where t is a positive real number. It has been conjectured that there exists a vertex of degree 2 in every minimally 1-tough graph. In this paper, we completely determine the structure of minimally 1-tough graphs with independence number not exceeding 3 and thus confirm the conjecture for this class of graphs.