Signed 2-independence in digraphs
نویسندگان
چکیده
منابع مشابه
Note on Upper Bound Signed 2-independence in Digraphs
Let D be a finite digraph with the vertex set V (D) and arc set A(D). A two-valued function f : V (D) → {−1, 1} defined on the vertices of a digraph D is called a signed 2-independence function if f(N−[v]) ≤ 1 for every v in D. The weight of a signed 2-independence function is f(V (D)) = ∑ v∈V (D) f(v). The maximum weight of a signed 2independence function of D is the signed 2-independence numb...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2012
ISSN: 0012-365X
DOI: 10.1016/j.disc.2011.09.009