Sum List Coloring Block Graphs
نویسنده
چکیده
A graph is f -choosable if for every collection of lists with list sizes specified by f there is a proper coloring using colors from the lists. We characterize f -choosable functions for block graphs (graphs in which each block is a clique, including trees and line graphs of trees). The sum choice number is the minimum over all choosable functions f of the sum of the sizes in f . The sum choice number of any graph is at most the number of vertices plus the number of edges. We show that this bound is tight for block graphs.
منابع مشابه
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عنوان ژورنال:
- Graphs and Combinatorics
دوره 20 شماره
صفحات -
تاریخ انتشار 2004