Constructions of bipartite graphs from finite geometries
نویسندگان
چکیده
We construct an incidence structure using certain points and lines in finite projective spaces. The structural properties of the associated bipartite incidence graphs are analyzed. These n×n bipartite graphs provide constructions of C6-free graphs with Ω(n4/3) edges, C10-free graphs with Ω(n6/5) edges, and Θ(7, 7, 7)-free graphs with Ω(n8/7) edges. Each of these bounds is sharp in order of magnitude.
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عنوان ژورنال:
- Journal of Graph Theory
دوره 49 شماره
صفحات -
تاریخ انتشار 2005