A note concerning paths and independence number in digraphs
نویسندگان
چکیده
منابع مشابه
Edge-disjoint paths in digraphs with bounded independence number
A digraph H is infused in a digraph G if the vertices of H are mapped to vertices of G (not necessarily distinct), and the edges of H are mapped to edge-disjoint directed paths of G joining the corresponding pairs of vertices of G. The algorithmic problem of determining whether a fixed graph H can be infused in an input graph G is polynomial-time solvable for all graphs H (using paths instead o...
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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: 1990
ISSN: 0012-365X
DOI: 10.1016/0012-365x(90)90210-9