Line Graphs and Forbidden Induced Subgraphs
نویسندگان
چکیده
Beineke and Robertson independently characterized line graphs in terms of nine forbidden induced subgraphs. In 1994, S8 olte s gave another characterization, which reduces the number of forbidden induced subgraphs to seven, with only five exceptional cases. A graph is said to be a dumbbell if it consists of two complete graphs sharing exactly one common edge. In this paper, we show that a graph with minimum degree at least seven that is not a dumbbell is a line graph if and only if it does not contain three forbidden induced subgraphs including K1, 3 and K5&e. Applications of our main results to other forbidden induced subgraph characterizations of line graphs and to hamiltonian line graphs are also discussed. 2001
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 82 شماره
صفحات -
تاریخ انتشار 2001