On Neighbor-Distinguishing Index of Planar Graphs

نویسندگان

  • Mirko Hornák
  • Danjun Huang
  • Wei-Fan Wang
چکیده

A proper edge colouring of a graph G without isolated edges is neighbour-distinguishing if any two adjacent vertices have distinct sets consisting of colours of their incident edges. The neighbour-distinguishing index of G is the minimum number ndi(G) of colours in a neighbour-distinguishing edge colouring of G. According to a conjecture by Zhang, Liu and Wang (2002), ndi(G) ≤ ∆(G) + 2 provided that G is a connected graph of order at least 6. The conjecture is proved for planar graphs G with ∆(G) ≥ 12.

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عنوان ژورنال:
  • Journal of Graph Theory

دوره 76  شماره 

صفحات  -

تاریخ انتشار 2014