Consecutive Colouring of Oriented Graphs
نویسندگان
چکیده
Abstract We consider arc colourings of oriented graphs such that for each vertex the colours all out-arcs incident with and in-arcs form intervals. prove existence a colouring is an NP-complete problem. give solution problem r -regular graphs, transitive tournaments, small maximum degree, order some other classes graphs. state conjecture graph there exists consecutive colourable orientation confirm complete 2-degenerate planar girth at least 8, bipartite arboricity most two include Additionally, we true perfect consecutively forbidden class
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ژورنال
عنوان ژورنال: Results in Mathematics
سال: 2021
ISSN: ['1420-9012', '1422-6383']
DOI: https://doi.org/10.1007/s00025-021-01505-3