Chordality and 2-factors in Tough Graphs
نویسندگان
چکیده
A graph G is chordal if it contains no chordless cycle of length at least four and is k-chordal if a longest chordless cycle in G has length at most k. In this note it is proved that all 2 -tough 5-chordal graphs have a 2-factor. This result is best possible in two ways. Examples due to Chvátal show that for all > 0 there exists a ( 2 − )-tough chordal graph with no 2-factor. Furthermore, examples due to Bauer and Schmeichel show that the result is false for 6chordal graphs.
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 99 شماره
صفحات -
تاریخ انتشار 2000