Independent sets and 2-factors in edge-chromatic-critical graphs
نویسندگان
چکیده
In 1968, Vizing made the following two conjectures for graphs which are critical with respect to the chromatic index: (1) every critical graph has a 2-factor, and (2) every independent vertex set in a critical graph contains at most half of the vertices. We prove both conjectures for critical graphs with many edges, and determine upper bounds for the size of independent vertex sets in those graphs.
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عنوان ژورنال:
- Journal of Graph Theory
دوره 45 شماره
صفحات -
تاریخ انتشار 2004