A Note on the Acquaintance Time of Random Graphs

نویسندگان

  • Bill Kinnersley
  • Dieter Mitsche
  • Pawel Pralat
چکیده

In this short note, we prove a conjecture of Benjamini, Shinkar, and Tsur on the acquaintance time AC(G) of a random graph G ∈ G(n, p). It is shown that asymptotically almost surely AC(G) = O(log n/p) for G ∈ G(n, p), provided that pn−log n−log log n→∞ (that is, above the threshold for Hamiltonicity). Moreover, we show a matching lower bound for dense random graphs, which also implies that asymptotically almost surely Kn cannot be covered with o(log n/p) copies of a random graph G ∈ G(n, p), provided that pn > n1/2+ε and p < 1 − ε for some ε > 0. We conclude the paper with a small improvement on the general upper bound showing that for any n-vertex graph G, we have AC(G) = O(n2/ log n).

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عنوان ژورنال:
  • Electr. J. Comb.

دوره 20  شماره 

صفحات  -

تاریخ انتشار 2013