псевдоокружность
Sign in to saveThe pseudocircle is the finite topological space X consisting of four distinct points {a,b,c,d} with the following non-Hausdorff topology: \{\{a,b,c,d\}, \{a,b,c\}, \{a,b,d\}, \{a,b\}, \{a\}, \{b\}, \varnothing\}.
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Псевдоокружность — конечное топологическое пространство, неотличимое от окружности с точки зрения алгебраической топологии.
Abstract from DBpedia / Wikipedia · CC BY-SA
Connections
circle
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mathematical proof
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digital object identifier
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continuous function
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union
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isomorphism
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unit circle
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intersection
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topological space
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Cambridge University Press
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algebraic topology
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open set
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disjoint sets
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category
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Hausdorff space
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general topology
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homology
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partially ordered set
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functor
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separation axiom
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