Lower Bounds for the Exponential Domination Number of Cm × Cn
نویسندگان
چکیده
A vertex v in an exponential dominating set assigns weight ( 1 2 )dist(v,u) to vertex u. An exponential dominating set of a graph G is a subset of V (G) such that every vertex in V (G) has been assigned a sum weight of at least 1. In this paper the exponential dominating number for the graph Cm × Cn, denoted by γe(Cm × Cn) is discussed. Anderson et. al. [1] proved that mn 15.875 ≤ γe(Cm × Cn) ≤ mn 13 and conjectured that mn 13 is also the asymptotic lower bound. We use a linear programing approach to sharpen the lower bound to mn 13.7619+ (m,n) .
منابع مشابه
On Exponential Domination of Cm × Cn
An exponential dominating set of graph G = (V,E) is a subset D ⊆ V such that ∑ w∈D( 1 2 )d(v,w)−1 ≥ 1 for every v ∈ V, where d(v, w) is the distance between vertices v and w. The exponential domination number, γe(G), is the smallest cardinality of an exponential dominating set. Lower and upper bounds for γe(Cm × Cn) are determined and it is shown that limm,n→∞ γe(Cm×Cn) mn ≤ 1 13 . Two connecti...
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تاریخ انتشار 2016