On Edge-Colouring Indifference Graphs
نویسندگان
چکیده
Vizing's theorem states that the chromatic index 0 (G) of a graph G is either the maximum degree (G) or (G) + 1. A graph G is called overfull if jE(G)j > (G)bjV (G)j=2c. A suucient condition for 0 (G) = (G) + 1 is that G contains an overfull subgraph H with (H) = (G). Plantholt proved that this condition is necessary for graphs with a universal vertex. In this paper, we conjecture that, for indiierence graphs, this is also true. As supporting evidence, we prove this conjecture for general graphs with three maximal cliques and with no universal vertex, and for indiierence graphs with odd maximum degree. For the latter subclass, we prove that 0 = .
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