Número da sorte e grafos exoplanares livres de triângulos
Abstract
An additive coloring of a graph G = (V,E) is a function c : V → {1, 2, . . . , k} such that, for every edge uv ∈ E, we have Sc(u) ≠ Sc(v), where Sc(u) = ∑v∈NG(u) c(v). The lucky number of a graph G, denoted by η(G), is the smallest value of k such that exists an additive coloring c. In this work, we show that if G is a triangle-free outerplanar graph, then η(G) ≤ 6. Moreover, we determine the lucky number for Loupekine Snarks.
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