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arXiv · 1905.06595

Trees whose even-degree vertices induce a path are antimagic

Antoni Lozano·Mercè Mora·Carlos Seara·Joaquín Tey
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Abstract

An antimagic labeling a connected graph $G$ is a bijection from the set of edges $E(G)$ to $\{1,2,\dots,|E(G)|\}$ such that all vertex sums are pairwise distinct, where the vertex sum at vertex $v$ is the sum of the labels assigned to edges incident to $v$. A graph is called antimagic if it has an antimagic labeling. In 1990, Hartsfield and Ringel conjectured that every simple connected graph other than $K_2$ is antimagic; however, the conjecture remains open, even for trees. In this note we prove that trees whose vertices of even degree induce a path are antimagic, extending a result given by Liang, Wong, and Zhu [Discrete Math. 331 (2014) 9--14].

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Antoni Lozano, Mercè Mora, Carlos Seara, Joaquín Tey. 2019-05-16. Trees whose even-degree vertices induce a path are antimagic. https://doi.org/10.7151/dmgt.2322

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