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Rainbow matchings in bipartite multigraphs
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Suppose that k is a non-negative integer and a bipartite multigraph G is the union of $$\begin{aligned} N=\left\lfloor \frac{k+2}{k+1}n\right\rfloor -(k+1) \end{aligned}$$matchings \(M_1,\dots ,M_N\), each of size n. We show that G has a rainbow matching of size \(n-k\), i.e. a matching of size \(n-k\) with all edges coming from different \(M_i\)’s. Several choices of the parameter k relate to known results and conjectures.KeywordsFactorizationsRainbow matchingsRyser’s conjectureReferences1.R. Aharoni, personal communication2.R. Aharoni, E. Berger, Rainbow matchings in \(r\)-partite \(r\)-graphs. Electron. J. Combin. 16(1), R119 (2009)MathSciNetMATHGoogle Scholar3.R. Aharoni, P. Charbit, D. Howard, On a generalization of the Ryser–Brualdi–Stein conjecture. J. Graph Theory 78(2), 143–156 (2015)MathSciNetCrossRefMATHGoogle Scholar4.R.A. Brualdi, H.J. Ryser, Combinatorial Matrix Theory (Cambridge University Press, Cambridge, UK, 1991)CrossRefMATHGoogle Scholar5.A.E. 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A 24, 235–237 (1978)MathSciNetCrossRefMATHGoogle ScholarCopyright information© Akadémiai Kiadó, Budapest, Hungary 2016Authors and AffiliationsJános Barát1András Gyárfás2Email authorGábor N. Sárközy231.MTA-ELTE Geometric and Algebraic Combinatorics Research GroupBudapestHungary2.Alfréd Rényi Institute of MathematicsHungarian Academy of SciencesBudapestHungary3.Computer Science DepartmentWorcester Polytechnic InstituteWorcesterUSA About this article CrossMark Publisher Name Springer Netherlands Print ISSN 0031-5303 Online ISSN 1588-2829 About this journal Reprints and Permissions Article actions .buybox { margin: 16px 0 0; position: relative; } .buybox { font-family: Source Sans Pro, Helvetica, Arial, sans-serif; font-size: 14px; font-size: .875rem; } .buybox { zoom: 1; } .buybox:after, .buybox:before { content: ''; display: table; } .buybox:after { clear: both; } /*---------------------------------*/ .buybox .buybox__header { border: 1px solid #b3b3b3; border-bottom: 0; padding: 8px 12px; 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