On the Number of Edges in a Minimum C6-Saturated Graph

نویسندگان

  • Mingchao Zhang
  • Song Luo
  • Maiko Shigeno
چکیده

A graph is said to be Ck-saturated if it contains no cycles of length k but does contain such a cycle after the addition of any edge in the complement of the graph. Determining the minimum size of Ck-saturated graphs is one of the interesting problems on extremal graphs. The exact minimum sizes are known for k = 3, 4 and 5, but only general bounds are shown for k ≥ 6. This paper deals with bounds of the minimum size when k = 6. It is shown that the minimum size of a C6-saturated graph on n vertices is no greater than � 3n−3 2 � and no less than � 7n 6 � − 2. This lower bound, which is first proposed exclusively for the C6-saturated graphs, significantly improves the best previously known lower bound.

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عنوان ژورنال:
  • Graphs and Combinatorics

دوره 31  شماره 

صفحات  -

تاریخ انتشار 2015