A topological space has the strong Pytkeev property at a point if there exists a countable family of subsets of such that for each neighborhood and subset accumulating at , there is a set such that and is infinite. We prove that for any -space and any space with the strong Pytkeev property at a point the function space has the strong Pytkeev property at the constant function . If the space is rectifiable, then the function space is rectifiable and has the strong Pytkeev property at each point. We also prove that for any pointed spaces , , with the strong Pytkeev property their Tychonoff product and their small box-product both have the strong Pytkeev property at the distinguished point. We prove that a sequential rectifiable space has the strong Pytkeev property if and only if is metrizable or contains a clopen submetrizable -subspace. A locally precompact topological group is metrizable if and only if it contains a dense subgroup with the strong Pytkeev property.

生成讲解博客的中文版本

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