Perfect graphs with unique P4-structure

نویسنده

  • Stefan Hougardy
چکیده

We will extend Reed's Semi-Strong Perfect Graph Theorem by proving that unbreakable C 5-free graphs diierent from a C 6 and its complement have unique P 4-structure.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

On Some Cograph Extensions and Their Algorithms

This paper reviews some classes of graphs related to cographs. The characterization of cographs by which there is no induced path on three edges (P4) is relaxed in various ways. Considered are classes of graphs that are uniquely representable by trees. Three such classes studied here are: P4-reducible, P4-sparse and P4-extendible graphs. In addition, we show that the class of P4-lite graphs has...

متن کامل

Split-Perfect Graphs: Characterizations and Algorithmic Use

Two graphs G and H with the same vertex set V are P4-isomorphic if every four vertices {a, b, c, d} ⊆ V induce a chordless path (denoted by P4) in G if and only if they induce a P4 in H. We call a graph split-perfect if it is P4-isomorphic to a split graph (i.e., a graph being partitionable into a clique and a stable set). This paper characterizes the new class of split-perfect graphs using the...

متن کامل

On hereditary properties of composition graphs

The composition graph of a family of n+1 disjoint graphs {Hi : 0 ≤ i ≤ n} is the graph H obtained by substituting the n vertices of H0 respectively by the graphs H1, H2, ..., Hn. If H has some hereditary property P , then necessarily all its factors enjoy the same property. For some sort of graphs it is sufficient that all factors {Hi : 0 ≤ i ≤ n} have a certain common P to endow H with this P ...

متن کامل

On P4-tidy graphs

We study the P4-tidy graphs, a new class defined by Rusu [30] in order to illustrate the notion of P4-domination in perfect graphs. This class strictly contains the P4-extendible graphs and the P4-lite graphs defined by Jamison & Olariu in [19] and [23] and we show that the P4-tidy graphs and P4-lite graphs are closely related. Note that the class of P4-lite graphs is a class of brittle graphs ...

متن کامل

Anti-forcing number of some specific graphs

Let $G=(V,E)$ be a simple connected graph. A perfect matching (or Kekul'e structure in chemical literature) of $G$ is a set of disjoint edges which covers all vertices of $G$. The anti-forcing number of $G$ is the smallest number of edges such that the remaining graph obtained by deleting these edges has a unique perfect matching and is denoted by $af(G)$. In this paper we consider some specifi...

متن کامل

ذخیره 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 نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Discrete Mathematics

دوره 165-166  شماره 

صفحات  -

تاریخ انتشار 1997