ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

Discussiones Mathematicae Graph Theory

IMPACT FACTOR 2018: 0.741

SCImago Journal Rank (SJR) 2018: 0.763

Rejection Rate (2018-2019): c. 84%

Discussiones Mathematicae Graph Theory


Discussiones Mathematicae Graph Theory 16(1) (1996) 5-16
DOI: 10.7151/dmgt.1019


H. Galeana-Sánchez and V. Neumann-Lara

Zona Comercial, Apartado 70-637
04511 México, D.F. MEXICO


A digraph D is said to satisfy the k-Meyniel's condition if each odd directed cycle of D has at least k diagonals. The study of the k-Meyniel's condition has been a source of many interesting problems, questions and results in the development of Kernel Theory. In this paper we present a method to construct a large variety of kernel-perfect (resp. critical kernel-imperfect) digraphs which satisfy the k-Meyniel's condition.

Primary keywords: digraph, kernel, independent set of vertices, absorbing set of vertices, kernel-perfect digraph, critical-kernel-imperfect digraph, τ-system, τ1-system.

Secondary keywords: indepedent kernel modulo Q, co-rooted tree, τ-construction, τ1-construction.

1991 Mathematics Subject Classification: 05C20.


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