On Deeply Critical Oriented Cliques
نویسندگان
چکیده
In this work we consider arc criticality in colourings of oriented graphs. We study deeply critical graphs, those graphs for which the removal any results a decrease chromatic number by 2. prove existence cliques every odd order \(n\ge 9\), closing an open question posed Borodin et al. [Journal Combinatorial Theory, Series B, 81(1):150–155, 2001]. Additionally, non-existence among family circulant even order.
منابع مشابه
On Deeply Critical Oriented Graphs
For every positive integer k, we present an oriented graph G k such that deleting any vertex of G k decreases its oriented chromatic number by at least k and deleting any arc decreases the oriented chromatic number of G k by two. 2001 Academic Press
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ژورنال
عنوان ژورنال: Trends in mathematics
سال: 2021
ISSN: ['2297-024X', '2297-0215']
DOI: https://doi.org/10.1007/978-3-030-83823-2_101