Bounding cochordal cover number of graphs via vertex stretching

Document Type: Research Paper


‎‎Science and Research Branch‎, ‎Islamic Azad University‎ ‎(IAU)‎, ‎Tehran‎, ‎Iran.


It is shown that when a special vertex stretching is applied to a graph, the cochordal cover number of the graph increases exactly by one, as it happens to its induced matching number and (Castelnuovo-Mumford) regularity. As a consequence, it is shown that the induced matching number and cochordal cover number of a special vertex stretching of a graph G are equal provided G is well-covered bipartite or weakly chordal graph.


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