Sierpinski space
From HandWiki
connected colon
The Sierpinski space is a particular topological space. It consists of the set $\{a,b\}$ with open sets $\{ \emptyset, \{a\}, \{a,b\} \}$.
References
- Steen, Lynn Arthur; Seebach, J.Arthur jun. Counterexamples in topology (2nd ed.) Springer (1978) ISBN 0-387-90312-7 Template:ZBL
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