Edge-colouring and total-colouring chordless graphs

نویسندگان

  • Raphael Machado
  • Celina M. H. de Figueiredo
  • Nicolas Trotignon
چکیده

A graph G is chordless if no cycle in G has a chord. In the present work we investigate the chromatic index and total chromatic number of chordless graphs. We describe a known decomposition result for chordless graphs and use it to establish that every chordless graph of maximum degree ∆ ≥ 3 has chromatic index ∆ and total chromatic number ∆+1. The proofs are algorithmic in the sense that we actually output an optimal colouring of a graph instance in polynomial time.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 313  شماره 

صفحات  -

تاریخ انتشار 2013