A Note on Chromatic Sum
نویسندگان
چکیده
The chromatic sum Σ(G) of a graph G is the smallest sum of colors among of proper coloring with the natural number. In this paper, we introduce a necessary condition for the existence of graph homomorphisms. Also, we present Σ(G) < χf (G)|G| for every graph G.
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ورودعنوان ژورنال:
- Ars Comb.
دوره 116 شماره
صفحات -
تاریخ انتشار 2014