Title of article :
Trees in greedy colorings of hypergraphs
Author/Authors :
Gyarfas، نويسنده , , Andr?s and Lehel، نويسنده , , Jen?، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2011
Abstract :
It is a well-known proposition that every graph of chromatic number larger than t contains every tree with t edges. The ‘standard’ reasoning is that such a graph must contain a subgraph of minimum degree at least t . Bohman, Frieze, and Mubayi noticed that, although this argument does not work for hypergraphs, it is still possible that the proposition holds for hypergraphs as well. Indeed, Loh recently proved that every uniform hypergraph of chromatic number larger than t contains every hypertree with t edges.
e observe that the basic property of the well-known greedy algorithm immediately implies a much more general result (with a conceptually simpler proof): if the greedy algorithm colors the vertices of an r -uniform hypergraph with more than t colors then the hypergraph contains every r -uniform hypertree with t edges.
Keywords :
Subtrees in graphs , chromatic number , Greedy coloring
Journal title :
Discrete Mathematics
Journal title :
Discrete Mathematics