A subset A of a continuum X is called Ƭ-closed set if Ƭ(A) = A, where Ƭ denotes the Jones Ƭ- function. We give a characterization of Ƭ-closed sets and then we show a counterexample to a hypothesis by David P. Bellamy, Leobardo Fernández and Sergio Macías about Ƭ-closed sets if Ƭ is idempotent on X.
H. Abobaker and W. J. Charatonik, "T-Closed Sets," Topology and its Applications, vol. 222, pp. 274-277, Elsevier, May 2017.
The definitive version is available at https://doi.org/10.1016/j.topol.2017.02.066
Mathematics and Statistics
Keywords and Phrases
Continuum; Continuumwise connected; Exhaustive σ-continuum; T-closed sets; The set function T
International Standard Serial Number (ISSN)
Article - Journal
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