A characterization of projective-planar signed graphs
نویسندگان
چکیده
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:
- Discrete Mathematics
دوره 290 شماره
صفحات -
تاریخ انتشار 2005