Spelling suggestions: "subject:"05515 coloring off graphs anda hypergraph"" "subject:"05515 coloring off graphs ando hypergraph""
1 |
Extending List Colorings of Planar GraphsLoeb, Sarah 01 May 2011 (has links)
In the study of list colorings of graphs, we assume each vertex of a graph has a specified list of colors from which it may be colored. For planar graphs, it is known that there is a coloring for any list assignment where each list contains five colors. If we have some vertices that are precolored, can we extend this to a coloring of the entire graph? We explore distance constraints when we allow the lists to contain an extra color. For lists of length five, we fix $W$ as a subset of $V(G)$ such that all vertices in $W$ have been assigned colors from their respective lists. We give a new, simplified proof where there are a small number of precolored vertices on the same face. We also explore cases where $W=\{u,v\}$ and $G$ has a separating $C_3$ or $C_4$ between $u$ and $v$.
|
Page generated in 0.1225 seconds