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تسجيل مستخدم جديدOn excluded minors for classes of graphical matroids
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Frame matroids and lifted-graphic matroids are two distinct minor-closed classes of matroids, each of which generalises the class of graphic matroids. The class of quasi-graphic matroids, recently introduced by Geelen, Gerards, and Whittle, simultaneously generalises both the classes of frame and lifted-graphic matroids. Let $mathcal{M}$ be one of these three classes, and let $r$ be a positive integer. We show that $mathcal{M}$ has only a finite number of excluded minors of rank $r$.
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