Characterization of the Minimizing Graph of the Connected Graphs Whose Complements Are Bicyclic
نویسندگان
چکیده
In a certain class of graphs, a graph is called minimizing if the least eigenvalue of its adjacency matrix attains the minimum. A connected graph containing two or three cycles is called a bicyclic graph if its number of edges is equal to its number of vertices plus one. Let Gc 1,n and Gc 2,n be the classes of the connected graphs of order n whose complements are bicyclic with exactly two and three cycles, respectively. In this paper, we characterize the unique minimizing graph among all the graphs which belong to Gc n = Gc 1,n ∪ Gc 2,n, a class of the connected graphs of order n whose complements are bicyclic.
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