| Title:
|
Remarks on discretely absolutely star-Lindelöf spaces (English) |
| Author:
|
Song, Yan-Kui |
| Language:
|
English |
| Journal:
|
Czechoslovak Mathematical Journal |
| ISSN:
|
0011-4642 (print) |
| ISSN:
|
1572-9141 (online) |
| Volume:
|
58 |
| Issue:
|
3 |
| Year:
|
2008 |
| Pages:
|
823-831 |
| Summary lang:
|
English |
| . |
| Category:
|
math |
| . |
| Summary:
|
In this paper, we prove the following statements: \item {(1)} There exists a Hausdorff Lindelöf space $X$ such that the Alexandroff duplicate $A(X)$ of $X$ is not discretely absolutely star-Lindelöf. \item {(2)} If $X$ is a regular Lindelöf space, then $A(X)$ is discretely absolutely star-Lindelöf. \item {(3)} If $X$ is a normal discretely star-Lindelöf space with $e(X)< \omega _1$, then $A(X)$ is discretely absolutely star-Lindelöf. (English) |
| Keyword:
|
countably compact space |
| Keyword:
|
star-Lindelöf space |
| Keyword:
|
absolutely star-Lindelöf space |
| Keyword:
|
discretely absolutely star-Lindelöf |
| MSC:
|
54B10 |
| MSC:
|
54D20 |
| MSC:
|
54D55 |
| idZBL:
|
Zbl 1174.54015 |
| idMR:
|
MR2455940 |
| . |
| Date available:
|
2010-07-20T14:10:40Z |
| Last updated:
|
2020-07-03 |
| Stable URL:
|
http://hdl.handle.net/10338.dmlcz/140423 |
| . |
| Reference:
|
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| Reference:
|
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| Reference:
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| Reference:
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| Reference:
|
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| Reference:
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| Reference:
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| Reference:
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| Reference:
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| Reference:
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| Reference:
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| Reference:
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| Reference:
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| . |
