| Title:
|
A generalization of a generic theorem in the theory of cardinal invariants of topological spaces (English) |
| Author:
|
Ramírez-Páramo, Alejandro |
| Author:
|
Tapia-Bonilla, Noé Trinidad |
| Language:
|
English |
| Journal:
|
Commentationes Mathematicae Universitatis Carolinae |
| ISSN:
|
0010-2628 (print) |
| ISSN:
|
1213-7243 (online) |
| Volume:
|
48 |
| Issue:
|
1 |
| Year:
|
2007 |
| Pages:
|
177-187 |
| . |
| Category:
|
math |
| . |
| Summary:
|
The main goal of this paper is to establish a technical result, which provides an algorithm to prove several cardinal inequalities and relative versions of cardinal inequalities related to the well-known Arhangel'skii's inequality: If $X$ is a $T_2$-space, then $|X|\leq 2^{L(X)\chi (X)}$. Moreover, we will show relative versions of three well-known cardinal inequalities. (English) |
| Keyword:
|
cardinal functions |
| Keyword:
|
cardinal inequalities |
| MSC:
|
54A25 |
| idZBL:
|
Zbl 1199.54034 |
| idMR:
|
MR2338838 |
| . |
| Date available:
|
2009-05-05T17:02:05Z |
| Last updated:
|
2012-05-01 |
| Stable URL:
|
http://hdl.handle.net/10338.dmlcz/119647 |
| . |
| 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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| . |
