Title of article :
Planar graphs without 3-, 7-, and 8-cycles are 3-choosable
Author/Authors :
Dvo??k، نويسنده , , Zden?k and Lidick?، نويسنده , , Bernard and ?krekovski، نويسنده , , Riste، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2009
Abstract :
A graph G is k -choosable if every vertex of G can be properly colored whenever every vertex has a list of at least k available colors. Grötzsch’s theorem [4] states that every planar triangle-free graph is 3-colorable. However, Voigt [M. Voigt, A not 3-choosable planar graph without 3-cycles, Discrete Math. 146 (1995) 325–328] gave an example of such a graph that is not 3-choosable, thus Grötzsch’s theorem does not generalize naturally to choosability. We prove that every planar triangle-free graph without 7- and 8-cycles is 3-choosable.
Keywords :
Choosability , list-coloring , Planar graphs , Short cycles
Journal title :
Discrete Mathematics
Journal title :
Discrete Mathematics