Afrika Matematika

, Volume 30, Issue 1–2, pp 291–296 | Cite as

On maximal, minimal and mean open sets

  • Kallol Bhandhu Bagchi
  • Ajoy MukharjeeEmail author


We see that the real numbers system with the usual topology contains no minimal open sets. This observation instigates us to study topological spaces having no minimal and maximal open sets. We find that such topological spaces if connected are not cut-point spaces. We also characterize mean open sets in \(T_{1}\) connected topological spaces.


Minimal open set Maximal open set Mean open set Cut point Cut-point space Connected space 

Mathematics Subject Classification

54D20 54A05 54D30 



The authors are grateful to the reviewers for some kind comments and suggestions toward a few modifications in the contents of the paper.


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Copyright information

© African Mathematical Union and Springer-Verlag GmbH Deutschland, ein Teil von Springer Nature 2018

Authors and Affiliations

  1. 1.Department of MathematicsKalipada Ghosh Tarai MahavidyalayaDarjeelingIndia
  2. 2.Department of MathematicsSt. Joseph’s CollegeDarjeelingIndia

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