{ "id": "2305.03585", "version": "v1", "published": "2023-05-05T14:44:33.000Z", "updated": "2023-05-05T14:44:33.000Z", "title": "Quorum colorings of maximum cardinality in linear time for a subclass of perfect trees", "authors": [ "Rafik Sahbi", "Wissam Boumalha", "Asmaa Issad" ], "categories": [ "math.CO" ], "abstract": "A partition $\\pi=\\{V_{1},V_{2},...,V_{k}\\}$ of the vertex set $V$ of a graph $G$ into $k$ color classes $V_{i}$, with $1\\leq i\\leq k$ is called a quorum coloring of $G$ if for every vertex $v\\in V$, at least half of the vertices in the closed neighborhood $N[v]$ of $v$ have the same color as $v$. The maximum cardinality of a quorum coloring of $G$ is called the quorum coloring number of $G$ and is denoted by $\\psi_{q}(G)$. A quorum coloring of order $\\psi_{q}(G)$ is a $\\psi_{q}$-coloring. The determination of the quorum coloring number or design a linear-time algorithm computing it in a perfect $N$-ary tree has been posed recently as an open problem by Sahbi. In this paper, we answer this problem by designing a linear-time algorithm for finding both a $\\psi_{q}$-coloring and the quorum coloring number for every perfect tree whose the vertices at the same depth have the same degree.", "revisions": [ { "version": "v1", "updated": "2023-05-05T14:44:33.000Z" } ], "analyses": { "subjects": [ "05C15", "05C69" ], "keywords": [ "maximum cardinality", "perfect tree", "quorum coloring number", "linear time", "linear-time algorithm" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }