Title:
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On sums and products in a field (English) |
Author:
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Zhou, Guang-Liang |
Author:
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Sun, Zhi-Wei |
Language:
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English |
Journal:
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Czechoslovak Mathematical Journal |
ISSN:
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0011-4642 (print) |
ISSN:
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1572-9141 (online) |
Volume:
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72 |
Issue:
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3 |
Year:
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2022 |
Pages:
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817-823 |
Summary lang:
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English |
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Category:
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math |
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Summary:
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We study sums and products in a field. Let $F$ be a field with ${\rm ch}(F)\not =2$, where ${\rm {\rm ch} } (F)$ is the characteristic of $F$. For any integer $k\geq 4$, we show that any $x\in F$ can be written as $a_1+\dots +a_k$ with $a_1,\dots ,a_k\in F$ and $a_1\dots a_k=1$, and that for any $\alpha \in F \setminus \{0\}$ we can write every $x\in F$ as $a_1\dots a_k$ with $a_1,\dots ,a_k\in F$ and $a_1+\dots +a_k=\alpha $. We also prove that for any $x\in F$ and $k\in \{2,3,\dots \}$ there are $a_1,\dots ,a_{2k}\in F$ such that $a_1+\dots +a_{2k}=x=a_1\dots a_{2k}$. (English) |
Keyword:
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field |
Keyword:
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rational function |
Keyword:
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restricted sum |
Keyword:
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restricted product |
MSC:
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11D85 |
MSC:
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11P99 |
MSC:
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11T99 |
idZBL:
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Zbl 07584104 |
idMR:
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MR4467944 |
DOI:
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10.21136/CMJ.2021.0184-21 |
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Date available:
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2022-08-22T08:24:17Z |
Last updated:
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2024-10-04 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/150619 |
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Reference:
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[1] Elkies, N. D.: On the areas of rational triangles or how did Euler (and how can we) solve $xyz(x+y+z)=a$?.Available at \let \relax\brokenlink{http://www.math.harvard.edu/ elkies/{euler_14t.pdf}} (2014), 50 pages. |
Reference:
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[2] Klyachko, A. A., Mazhuga, A. M., Ponfilenko, A. N.: Balanced factorisations in some algebras.Available at https://arxiv.org/abs/1607.01957 (2016), 4 pages. |
Reference:
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[3] Klyachko, A. A., Vassilyev, A. N.: Balanced factorisations.Available at https://arxiv.org/abs/1506.01571 (2015), 8 pages. MR 3593641 |
Reference:
|
[4] Zypen, D. van der: Question on a generalisation of a theorem by Euler.Question 302933 at MathOverflow, June 16, 2018. Available at http://mathoverflow.net/questions/302933. |
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