Graphic splitting of cographic matroids
نویسنده
چکیده
In this paper, we obtain a forbidden minor characterization of a cographic matroid M for which the splitting matroid Mx,y is graphic for every pair x, y of elements of M .
منابع مشابه
On cographic matroids and signed-graphic matroids
We prove that a connected cographic matroid of a graph G is the bias matroid of a signed graph Σ iff G imbeds in the projective plane. In the case that G is nonplanar, we also show that Σ must be the projective-planar dual signed graph of an actual imbedding of G in the projective plane. As a corollary we get that, if G1, . . . , G29 denote the 29 nonseparable forbidden minors for projective-pl...
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ورودعنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 35 شماره
صفحات -
تاریخ انتشار 2015