Circular flow number of highly edge connected signed graphs
نویسندگان
چکیده
منابع مشابه
The edge domination number of connected graphs
A subset X of edges in a graph G is called an edge dominating set of G if every edge not in X is adjacent to some edge in X. The edge domination number γ′(G) of G is the minimum cardinality taken over all edge dominating sets of G. Let m,n and k be positive integers with n − 1 ≤ m ≤ (n 2 ) , G(m,n) be the set of all non-isomorphic connected graphs of order n and size m, and G(m,n; k) = {G ∈ G(m...
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Let $kgeq 1$ be an integer, and $G=(V,E)$ be a finite and simplegraph. The closed neighborhood $N_G[e]$ of an edge $e$ in a graph$G$ is the set consisting of $e$ and all edges having a commonend-vertex with $e$. A signed Roman edge $k$-dominating function(SREkDF) on a graph $G$ is a function $f:E rightarrow{-1,1,2}$ satisfying the conditions that (i) for every edge $e$of $G$, $sum _{xin N[e]} f...
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We show that every 6-edge connected graph admits a circulation whose range lies in the interval 1; 3). The circular ow number c (G) of a ((nite) graph G is deened by c (G) = inffr 2 R: some orientation ~ G admits a circulation f : E(~ G) ! 1; r ? 1]g: This parameter is a reenement of the well studied ow number (G) := d c (G)e, which was introduced by Tutte as a dual to the chromatic number. Sin...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 2015
ISSN: 0095-8956
DOI: 10.1016/j.jctb.2014.12.002