Minimum Size of n-Factor-Critical Graphs and k-Extendable Graphs
نویسندگان
چکیده
We determine the minimum size of n-factor-critical graphs and that of k-extendable bipartite graphs, by considering Harary graphs and related graphs. Moreover, we determine the minimum size of k-extendable non-bipartite graphs for k = 1, 2, and pose a related conjecture for general k.
منابع مشابه
Connectivity of k-extendable graphs with large k
Let G be a simple connected graph on 2n vertices with perfect matching. For a given positive integer k (06 k6 n − 1), G is k-extendable if any matching of size k in G is contained in a perfect matching of G. It is proved that if G is a k-extendable graph on 2n vertices with k¿ n=2, then either G is bipartite or the connectivity of G is at least 2k. As a corollary, we show that if G is a maximal...
متن کاملConstruction for bicritical graphs and k-extendable bipartite graphs
A graphG is said to be bicritical ifG−u− v has a perfect matching for every choice of a pair of points u and v. Bicritical graphs play a central role in decomposition theory of elementary graphs with respect to perfect matchings. As Plummer pointed out many times, the structure of bicritical graphs is far from completely understood. This paper presents a concise structure characterization on bi...
متن کاملThe minus k-domination numbers in graphs
For any integer , a minus k-dominating function is afunction f : V (G) {-1,0, 1} satisfying w) for every vertex v, where N(v) ={u V(G) | uv E(G)} and N[v] =N(v)cup {v}. The minimum of the values of v), taken over all minusk-dominating functions f, is called the minus k-dominationnumber and is denoted by $gamma_k^-(G)$ . In this paper, we introduce the study of minu...
متن کاملOn k-factor-critical graphs
A graph is said to be k-factor-critical if the removal of any set of k vertices results in a graph with a perfect matching. We study some properties of k-factor-critical graphs and show that many results on q-extendable graphs can be improved using this concept.
متن کاملN-extendability of Line Graphs, Power Graphs, and Total Graphs
A graph G that has a perfect matching is n-extendable if every matching of size n lies in a perfect matching of G. We show that when the connectivity of a line graph, power graph, or total graph is sufficiently large then it is n-extendable. Specifically: if G has even size and is (2n + 1)edge-connected or (n + 2)-connected, then its line graph is n-extendable; if G has even order and is (n + 1...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Graphs and Combinatorics
دوره 28 شماره
صفحات -
تاریخ انتشار 2012