Department of Mathematics, School of Science, Beijing Institute of Technology, Beijing 100081, China; Department of Mathematics, Langfang Teachers College, Langfang, Hebei 065000, China
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Department of Mathematics, School of Science, Beijing Institute of Technology, Beijing 100081, China
Let G=(V,E) be a simple graph. For any real valued function f:V →R, the weight of f is f(V) = ∑f(v) over all vertices v∈V . A signed total dominating function is a function f:V→{-1,1} such that f(N(v)) ≥1 for every vertex v∈V . The signed total domination number of a graph G equals the minimum weight of a signed total dominating function on G . In this paper, some properties of the signed total domination number of a graph G are discussed.