Kernel perfect and critical kernel imperfect digraphs structure
نویسندگان
چکیده
منابع مشابه
Kernel perfect and critical kernel imperfect digraphs structure
A kernel N of a digraph D is an independent set of vertices of D such that for every w ∈ V (D)−N there exists an arc from w to N . If every induced subdigraph of D has a kernel, D is said to be a kernel perfect digraph. Minimal non-kernel perfect digraph are called critical kernel imperfect digraph. If F is a set of arcs of D, a semikernel modulo F , S of D is an independent set of vertices of ...
متن کاملSome results on the structure of kernel-perfect and critical kernel-imperfect digraphs
A kernel N of a digraph D is an independent set of vertices of D such that for every w ∈ V (D) − N there exists an arc from w to N . The digraph D is said to be a kernel-perfect digraph when every induced subdigraph of D has a kernel. Minimal non kernel-perfect digraphs are called critical kernel imperfect digraphs. In this paper some new structural results concerning finite critical kernel imp...
متن کاملOn kernel-perfect critical digraphs
In this paper we investigate new sufficient conditions for a digraph to be kernel-perfect (KP) and some structural properties of kernel-perfect critical (KPC) digraphs. In particular, it is proved that the asymmetrical part of any KPC digraph is strongly connected. A new method to construct KPC digraphs is developed. The existence of KP and KPC digraphs with arbitrarily large dichromatic number...
متن کاملNew classes of critical kernel-imperfect digraphs
A kernel of a digraph D is a subset N ⊆ V (D) which is both independent and absorbing. When every induced subdigraph of D has a kernel, the digraph D is said to be kernel-perfect. We say that D is a critical kernel-imperfect digraph if D does not have a kernel but every proper induced subdigraph of D does have at least one. Although many classes of critical kernel-imperfect-digraphs have been c...
متن کاملOn a class of kernel-perfect and kernel-perfect-critical graphs
Chilakamarri, K.B. and P. Hamburger, On a class of kernel-perfect and kernel-perfect-critical graphs, Discrete Mathematics 118 (1993) 253-257. In this note we present a construction of a class of graphs in which each of the graphs is either kernel-perfect or kernel-perfect-critical. These graphs originate from the theory of games (Von Neumann and Morgenstern). We also find criteria to distingui...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Electronic Notes in Discrete Mathematics
سال: 2007
ISSN: 1571-0653
DOI: 10.1016/j.endm.2007.01.054