ArticleOriginal scientific text
Title
On the existence of a cycle of length at least 7 in a (1,≤ 2)-twin-free graph
Authors 1, 1, 1, 2
Affiliations
- Institut Telecom - Telecom ParisTech & Centre National de la Recherche Scientifique - LTCI UMR 5141, 46, rue Barrault, 75634 Paris Cedex 13, France
- Centre National de la Recherche Scientifique - LTCI UMR 5141 & Telecom ParisTech, 46, rue Barrault, 75634 Paris Cedex 13, France
Abstract
We consider a simple, undirected graph G. The ball of a subset Y of vertices in G is the set of vertices in G at distance at most one from a vertex in Y. Assuming that the balls of all subsets of at most two vertices in G are distinct, we prove that G admits a cycle with length at least 7.
Keywords
undirected graph, twin subsets, identifiable graph, distinguishable graph, identifying code, maximum length cycle
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