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Title: Double Vizing fans in critical class two graphs
Abstract Let be a simple graph and be the chromatic index of . We call a ‐critical graphif for every edge of , where is maximum degree of . Let be an edge of ‐critical graph and be an (proper) edge ‐coloring of . Ane‐fanis a sequence of alternating vertices and distinct edges such that edge is incident with or , is another endvertex of and is missing at a vertex before for each with . In this paper, we prove that if , where and denote the degrees of vertices and , respectively, then colors missing at different vertices of are distinct. Clearly, a Vizing fan is an ‐fan with the restricting that all edges being incident with one fixed endvertex of edge . This result gives a common generalization of several recently developed new results on multifan, double fan, Kierstead path of four vertices, and broom. By treating some colors of edges incident with vertices of low degrees as missing colors, Kostochka and Stiebitz introduced ‐fan. In this paper, we also generalize the ‐fan from centered at one vertex to one edge.  more » « less
Award ID(s):
1855716 2154331
PAR ID:
10506016
Author(s) / Creator(s):
; ;
Publisher / Repository:
John Wiley
Date Published:
Journal Name:
Journal of Graph Theory
Volume:
103
Issue:
1
ISSN:
0364-9024
Page Range / eLocation ID:
48 to 65
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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