Projective-Planar Graphs with no K3, 4-Minor. II

نویسندگان

  • John Maharry
  • Daniel C. Slilaty
چکیده

The authors previously published an iterative process to generate a class of projectiveplanarK3,4-free graphs called ‘patch graphs’. They also showed that any simple, almost 4-connected, nonplanar, and projective-planar graph that is K3,4-free is a subgraph of a patch graph. In this paper, we describe a simpler and more natural class of cubic K3,4free projective-planar graphs which we call Möbius hyperladders. Furthermore, every simple, almost 4-connected, nonplanar, and projective-planar graph that is K3,4-free is a minor of a Möbius hyperladder. As applications of these structures we determine the page number of patch graphs and of Möbius hyperladders.

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عنوان ژورنال:
  • Journal of Graph Theory

دوره 86  شماره 

صفحات  -

تاریخ انتشار 2017