L(2, 1)-labelling of Circular-arc Graph
نویسندگان
چکیده
An (2,1) L -labelling of a graph ( , ) G V E = is 2,1( ) G λ a function f from the vertex set ( ) V G to the set of non-negative integers such that adjacent vertices get numbers at least two apart, and vertices at distance two get distinct numbers. The (2,1) L -labelling number denoted by 2,1( ) G λ of G is the minimum range of labels over all such labelling. In this article, it is shown that, for a circular-arc graph G , the upper bound of 2,1( ) G λ is 3ω ∆ + , where ∆ and ω represents the maximum degree of the vertices and size of maximum clique respectively.
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عنوان ژورنال:
- CoRR
دوره abs/1407.5488 شماره
صفحات -
تاریخ انتشار 2014