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Nonincrease of density and weak density under weakly normal functors

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Abstract

In this paper, it is proved that if a covariant functor ℱ: Comp → Comp is weakly normal, then d(ℱβ(X)) ≤ d(X) and wd(ℱβ(X)) ≤ wd(X) for any infinite Tychonoff space X.

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Authors and Affiliations

  1. Institute of Mathematics and Information Technologies, Academy of Sciences of Uzbekistan, Baku, Uzbekistan

    R. B. Beshimov

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  1. R. B. Beshimov
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Correspondence to R. B. Beshimov.

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Original Russian Text © R. B. Beshimov, 2008, published in Matematicheskie Zametki, 2008, Vol. 84, No. 4, pp. 527–531.

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Beshimov, R.B. Nonincrease of density and weak density under weakly normal functors. Math Notes 84, 493–497 (2008). https://doi.org/10.1134/S0001434608090216

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  • DOI: https://doi.org/10.1134/S0001434608090216

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