Contractible edges in minimally k-connected graphs

نویسندگان

  • Kiyoshi Ando
  • Atsushi Kaneko
  • Ken-ichi Kawarabayashi
چکیده

An edge of a k-connected graph is said to be k-contractible if the contraction of the edge results in a k-connected graph. In this paper, we prove that a (K1 + C4)-free minimally k-connected graph has a k-contractible edge, if incident to each vertex of degree k, there is an edge which is not contained in a triangle. This implies two previous results, one due to Thomassen and the other due to Kawarabayashi. © 2007 Elsevier B.V. All rights reserved.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 308  شماره 

صفحات  -

تاریخ انتشار 2002