V. Tzannes, "Two countable Hausdorff almost regular spaces every contiunous map of which into every Urysohn space is constant", International Journal of Mathematics and Mathematical Sciences, vol. 14, Article ID 425219, 6 pages, 1991. https://doi.org/10.1155/S0161171291000959
Two countable Hausdorff almost regular spaces every contiunous map of which into every Urysohn space is constant
We construct two countable, Hausdorff, almost regular spaces , having the following properties: (1) Every continuous map of (resp, ) into every Urysohn space is constant (hence, both spaces are connected). (2) For every point of (resp. of ) and for every open neighbourhood of this point there exists an open neighbourhood of it such that and every continuous map of into every Urysohn space is constant (hence both spaces are locally connected). (3) The space is first countable and the space nowhere first countable. A consequence of the above is the construction of two countable, (connected) Hausdorff, almost regular spaces with a dispersion point and similar properties. Unfortunately, none of these spaces is Urysohn.
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