Title:
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Does the endomorphism poset $P^P$ determine whether a finite poset $P$ is connected? An issue Duffus raised in 1978 (English) |
Author:
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Farley, Jonathan David |
Language:
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English |
Journal:
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Mathematica Bohemica |
ISSN:
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0862-7959 (print) |
ISSN:
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2464-7136 (online) |
Volume:
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148 |
Issue:
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4 |
Year:
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2023 |
Pages:
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435-446 |
Summary lang:
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English |
. |
Category:
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math |
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Summary:
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Duffus wrote in his 1978 Ph.D. thesis, ``It is not obvious that $P$ is connected and $P^P\cong Q^Q$ imply that $Q$ is connected'', where $P$ and $Q$ are finite nonempty posets. We show that, indeed, under these hypotheses $Q$ is connected and $P\cong Q$. (English) |
Keyword:
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(partially) ordered set |
Keyword:
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exponentiation |
Keyword:
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connected |
MSC:
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06A07 |
idZBL:
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Zbl 07790595 |
idMR:
|
MR4673829 |
DOI:
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10.21136/MB.2022.0010-22 |
. |
Date available:
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2023-11-23T12:33:02Z |
Last updated:
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2024-12-13 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/151965 |
. |
Reference:
|
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Reference:
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Reference:
|
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Reference:
|
[4] Duffus, D. A.: Toward a Theory of Finite Partially Ordered Sets: Ph.D. Thesis.University of Calgary, Calgary (1978). MR 2940856 |
Reference:
|
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Reference:
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Reference:
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Reference:
|
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Reference:
|
[9] Farley, J. D.: An issue raised in 1978 by a then-future editor-in-chief of the Journal ``Order'': Does the endomorphism poset of a finite connected poset tell us that the poset is connected?.Available at https://arxiv.org/abs/2005.03255v1 (2020), 12 pages. MR 4673829 |
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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