Homomorphism bounded classes of graphs
نویسندگان
چکیده
A class C of graphs is said to be H-bounded if each graph in the class C admits a homomorphism to H. We give a general necessary and sufficient condition for the existence of bounds with special local properties. This gives a new proof of Häggkvist-Hell theorem [5] and implies several cases of the existence of triangle free bounds for planar graphs.
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 27 شماره
صفحات -
تاریخ انتشار 2006