Displaying similar documents to “On Pascu Type α-Close-To-Star Functions”

Remarks on Star-Hurewicz Spaces

Yan-Kui Song (2013)

Bulletin of the Polish Academy of Sciences. Mathematics

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A space X is star-Hurewicz if for each sequence (𝒰ₙ: n ∈ ℕ) of open covers of X there exists a sequence (𝓥ₙ: n ∈ ℕ) such that for each n, 𝓥ₙ is a finite subset of 𝒰ₙ, and for each x ∈ X, x ∈ St(⋃ 𝓥ₙ,𝒰ₙ) for all but finitely many n. We investigate the relationship between star-Hurewicz spaces and related spaces, and also study topological properties of star-Hurewicz spaces.

Strong ƒ-Star Factors of Graphs

Zheng Yan (2015)

Discussiones Mathematicae Graph Theory

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Let G be a graph and f : V (G) → {2, 3, . . .}. A spanning subgraph F is called strong f-star of G if each component of F is a star whose center x satisfies degF (x) ≤ ƒ(x) and F is an induced subgraph of G. In this paper, we prove that G has a strong f-star factor if and only if oddca(G − S) ≤ ∑x∊S ƒ(x) for all S ⊂ V (G), where oddca(G) denotes the number of odd complete-cacti of G.