{ "id": "2411.12863", "version": "v1", "published": "2024-11-19T21:12:07.000Z", "updated": "2024-11-19T21:12:07.000Z", "title": "On corona of Konig-Egervary graphs", "authors": [ "Vadim E. Levit", "Eugen Mandrescu" ], "comment": "11 pages, 3 figures", "categories": [ "math.CO", "cs.DM" ], "abstract": "Let $\\alpha(G)$ denote the cardinality of a maximum independent set and $\\mu(G)$ be the size of a maximum matching of a graph $G=\\left( V,E\\right) $. If $\\alpha(G)+\\mu(G)=\\left\\vert V\\right\\vert $, then $G$ is a K\\\"{o}nig-Egerv\\'{a}ry graph, and $G$ is a $1$-K\\\"{o}nig-Egerv\\'{a}ry graph whenever $\\alpha(G)+\\mu(G)=\\left\\vert V\\right\\vert -1$. The corona $H\\circ\\mathcal{X}$ of a graph $H$ and a family of graphs $\\mathcal{X}=\\left\\{ X_{i}:1\\leq i\\leq\\left\\vert V(H)\\right\\vert \\right\\} $ is obtained by joining each vertex $v_{i}$ of $H$ to all the vertices of the corresponding graph $X_{i},i=1,2,...,\\left\\vert V(H)\\right\\vert $. In this paper we completely characterize graphs whose coronas are $k$-K\\\"{o}nig-Egerv\\'{a}ry graphs, where $k\\in\\left\\{ 0,1\\right\\} $.", "revisions": [ { "version": "v1", "updated": "2024-11-19T21:12:07.000Z" } ], "analyses": { "subjects": [ "05C69", "05C70", "G.2.2" ], "keywords": [ "konig-egervary graphs", "maximum independent set", "cardinality", "characterize graphs" ], "note": { "typesetting": "TeX", "pages": 11, "language": "en", "license": "arXiv", "status": "editable" } } }