Long cycles in subgraphs of (pseudo)random directed graphs

نویسندگان

  • Ido Ben-Eliezer
  • Michael Krivelevich
  • Benny Sudakov
چکیده

We study the resilience of random and pseudorandom directed graphs with respect to the property of having long directed cycles. For every 0 < γ < 1/2 we find a constant c = c(γ) such that the following holds. Let G = (V,E) be a (pseudo)random directed graph on n vertices and with at least a linear number of edges, and let G′ be a subgraph of G with (1/2 + γ)|E| edges. Then G′ contains a directed cycle of length at least (c − o(1))n. Moreover, there is a subgraph G′′ of G with (1/2 + γ − o(1))|E| edges that does not contain a cycle of length at least cn.

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عنوان ژورنال:
  • Journal of Graph Theory

دوره 70  شماره 

صفحات  -

تاریخ انتشار 2012