5-choosability of graphs with 2 crossings
نویسندگان
چکیده
We show that every graph with two crossings is 5-choosable. We also prove that every graph which can be made planar by removing one edge is 5-choosable. Key-words: list colouring, choosability, crossing number † Universidade Federal do Ceará, Departamento de Computaçao, Bloco 910, Campus do Pici, Fortaleza, Ceará, CEP 60455-760, Brasil. [email protected]; Partially supported by CNPq/Brazil. ‡ Projet Mascotte, I3S(CNRS, UNSA) and INRIA, 2004 route des lucioles, BP 93, 06902 Sophia-Antipolis Cedex, France. [email protected]; Partially supported by the ANR Blanc International ANR-09-blan-0373-01. ∗ This work was partially supported by Equipe Associée EWIN. in ria -0 05 93 42 6, v er si on 1 21 M ay 2 01 1 5-choisissabilité des graphes ayant deux croisements Résumé : Nous montrons que tout graphe ayant deux croisements est 5-choisissable. Nous prouvons également que tout graphe qui peut être rendu planaire par la suppression d’une arête est 5choisissable. Mots-clés : coloration sur listes, choisissabilité, nombre de croisements in ria -0 05 93 42 6, v er si on 1 21 M ay 2 01 1 5-choosability of graphs with 2 crossings 3
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