Colorings of Graphs Power
نویسنده
چکیده
In this paper some coloring properties of graphs power have been presented. In this regard, the helical graphs have been introduced and it was shown that they are hom-universal with respect to high odd-girth graphs whose lth power is bounded with a Kneser graph. In the sequel, we have considered Pentagon’s problem of Nešetřil which this problem is about the existence of high girth cubic graphs which are not homomorphic to the cycle of size five. Several problems which have close connection to Nešetřil’s problem have been introduced and their relevance have been presented.
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تاریخ انتشار 2008