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تسجيل مستخدم جديدThe Kirch space is topologically rigid
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The $Golomb$ $space$ (resp. the $Kirch$ $space$) is the set $mathbb N$ of positive integers endowed with the topology generated by the base consisting of arithmetic progressions $a+bmathbb N_0={a+bn:nge 0}$ where $ainmathbb N$ and $b$ is a (square-free) number, coprime with $a$. It is known that the Golomb space (resp. the Kirch space) is connected (and locally connected). By a recent result of Banakh, Spirito and Turek, the Golomb space has trivial homeomorphism group and hence is topologically rigid. In this paper we prove the topological rigidity of the Kirch space.
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