Stefan Janaqi, Laboratoire Leibniz, IMAG, Grenoble, France; F. Lescure, M. Maamoun, H. Meyniel, Equipe Combinatorie, CNRS, Université Paris VI, Paris, France
Abstract: We show that any digraph on $n\ge3$ vertices and with not less than $3n-3$ arcs is contractible onto ${}^*\!K_3$
Keywords: digraph, minor, contraction
Classification (MSC2000): 05C20
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