TIGHT TOUGHNESS CONDITION FOR FRACTIONAL (g, f, n)-CRITICAL GRAPHS
نویسندگان
چکیده
منابع مشابه
TIGHT TOUGHNESS CONDITION FOR FRACTIONAL (g, f, n)-CRITICAL GRAPHS
All graphs considered in this paper are finite, loopless, and without multiple edges. The notation and terminology used but undefined in this paper can be found in [2]. Let G be a graph with the vertex set V (G) and the edge set E(G). For a vertex x ∈ V (G), we use dG(x) and NG(x) to denote the degree and the neighborhood of x in G, respectively. Let δ(G) denote the minimum degree of G. For any...
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Let G be a graph of order p, and let a and b and n be nonnegative integers with 1 ≤ a ≤ b, and let g and f be two integer-valued functions defined on V (G) such that a ≤ g(x) ≤ f(x) ≤ b for all x ∈ V (G). A (g, f)-factor of graph G is defined as a spanning subgraph F of G such that g(x) ≤ dF (x) ≤ f(x) for each x ∈ V (G). Then a graph G is called a (g, f, n)-critical graph if after deleting any...
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Let G be a graph of order p, and let a, b and n be nonnegative integers with b ≥ a ≥ 2, and let f be an integer-valued function defined on V (G) such that a ≤ f(x) ≤ b for each x ∈ V (G). A fractional f -factor is a function h that assigns to each edge of a graph G a number in [0,1], so that for each vertex x we have dG(x) = f(x), where d h G(x) = ∑ e3x h(e) (the sum is taken over all edges inc...
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ژورنال
عنوان ژورنال: Journal of the Korean Mathematical Society
سال: 2014
ISSN: 0304-9914
DOI: 10.4134/jkms.2014.51.1.055