A Connected Countable Hausdorff Space
Copyright policy ) Bing, R. H.;
A Connected Countable Hausdorff Space
In Math. Ann. vol. 94 (1925) pp. 262-295, Urysohn gave an example of a connected Hausdorff space with only countably many points. Here is another. EXAMPLE 1. The points of the space are the rational points in the plane on or above the x-axis. If (a, b) is such a point and e>0, (a, b)+{(r, 0)1 either 1r-(a+b/31I2)|
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