List-colouring the square of a K4-minor-free graph

نویسندگان

  • Timothy J. Hetherington
  • Douglas R. Woodall
چکیده

Let G be a K4-minor-free graph with maximum degree . It is known that if ∈ {2, 3} then G2 is ( + 2)-degenerate, so that (G2) ch(G2) + 3. It is also known that if 4 then G2 is ( 3 2 + 1)-degenerate and (G2) 3 2 + 1. It is proved here that if 4 then G2 is 3 2 -degenerate and ch(G2) 3 2 + 1. These results are sharp. © 2007 Elsevier B.V. All rights reserved.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 308  شماره 

صفحات  -

تاریخ انتشار 2008