SOME REMARKS ON sn-METRIZABLE SPACES
نویسندگان
چکیده
This paper shows that sn-metrizable spaces can not be characterized as sequence-covering, compact, σ-images of metric spaces or sn-open, π, σ-images of metric spaces. Also, a space with a locally countable sn-network need not to be an sn-metrizable space. These results correct some errors on sn-metrizable spaces. AMS Mathematics Subject Classification (2000): 54C05, 54E35, 54E40
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Sn-metrizable Spaces and Related Matters
sn-networks were first introduced by Lin [12], which are the concept between weak bases and cs-networks. sn-metrizable spaces [6] (i.e., spaces with σ-locally finite sn-networks) are one class of generalized metric spaces, and they play an important role in metrization theory, see [6, 13]. In this paper, we give a mapping theorem on sn-metrizable spaces, discuss relationships among spaces with ...
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