On 2-Detour Subgraphs of the Hypercube
نویسندگان
چکیده
A spanning subgraph H of a graph G is a 2-detour subgraph of G if for each x, y ∈ V (G), dH(x, y) ≤ dG(x, y) + 2. We prove a conjecture of Erdős, Hamburger, Pippert, and Weakley by showing that for some positive constant c and every n, each 2-detour subgraph of the n-dimensional hypercube Qn has at least c log2 n · 2n edges.
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ورودعنوان ژورنال:
- Graphs and Combinatorics
دوره 24 شماره
صفحات -
تاریخ انتشار 2008