• Corpus ID: 119591566

A Summary of Problems and Results related to the Caccetta-Haggkvist Conjecture

  title={A Summary of Problems and Results related to the Caccetta-Haggkvist Conjecture},
  author={Blair D. Sullivan},
  journal={arXiv: Combinatorics},
This paper is an attempt to survey the current state of our knowledge on the Caccetta-Haggkvist conjecture and related questions. In January 2006 there was a workshop hosted by the American Institute of Mathematics in Palo Alto, on the Caccetta-Haggkvist conjecture, and this paper partly originated there, as a summary of the open problems and partial results presented at the workshop. This summary includes results and open problems related to Caccetta-Haggkvist, Seymour's Second Neighborhood… 
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  • Jian Shen
  • Mathematics
    J. Comb. Theory, Ser. B
  • 1998
Letcbe the smallest possible value such that every digraph onnvertices with minimum outdegree at leastcncontains a directed triangle. It was conjectured by Caccetta and Haggkvist in 1978 thatc=1/3.