Lindelöf number
From Encyclopedia of Mathematics
2020 Mathematics Subject Classification: Primary: 54A25 [MSN][ZBL]
density character
One of the cardinal characteristics of a topological space. The least infinite cardinal number $\tau$ such that every open covering has a subcovering of cardinality at most $\tau$.
References
- Mary Ellen Rudin, Lectures on Set Theoretic Topology, American Mathematical Society (1975) ISBN 0-8218-1673-X
How to Cite This Entry:
Lindelöf number. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Lindel%C3%B6f_number&oldid=54583
Lindelöf number. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Lindel%C3%B6f_number&oldid=54583