Abstract
For a Tychonoff space X, we will denote by USCp(X) (B1(X)) the set of all real-valued upper semicontinuous functions (the set of all Baire functions of class 1) defined on X endowed with the pointwise convergence topology.
In this paper we describe a class of Tychonoff spaces X for which the space USCp(X) is sequentially separable. Unexpectedly, it turns out that this class coincides with the class of spaces for which a stronger form of the sequential separability for the space B1(X) holds.
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Acknowledgements
The authors are grateful to Sergey V. Medvedev and the anonymous referee for making several suggestions which improved this paper.
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Osipov, A.V., Pytkeev, E.G. On some properties of the space of upper semicontinuous functions. Acta Math. Hungar. 157, 459–464 (2019). https://doi.org/10.1007/s10474-018-00906-1
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DOI: https://doi.org/10.1007/s10474-018-00906-1
Key words and phrases
- sequentially separable
- function space
- continuous function
- upper semicontinuous function
- Baire function of class 1