Strong Chromatic Index of 2-Degenerate Graphs


  • [This article was originally published online on 5 May 2012. In December 2012, a deficiency in the proof of Theorem 1 was acknowledged and corrected (see Acknowledgements)]. The corrected version was published on 20 February 2013.

  • Contract grant sponsor: National Science Council, Contract grant numbers: NSC98-2115-M-002-013-MY3 and NSC099-2811-M-002-042.


We prove that the strong chromatic index of a 2-degenerate graph is linear in the maximum degree Δ. This includes the class of all chordless graphs (graphs in which every cycle is induced) which in turn includes graphs where the cycle lengths are multiples of four, and settles a problem by Faudree et al. (Ars Combin 29(B) (1990), 205–211). © 2012 Wiley Periodicals, Inc. J. Graph Theory 73: 119–126, 2013