Title:
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Some generalizations of Olivier's theorem (English) |
Author:
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Faisant, Alain |
Author:
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Grekos, Georges |
Author:
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Mišík, Ladislav |
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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141 |
Issue:
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4 |
Year:
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2016 |
Pages:
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483-494 |
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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Let $\sum \limits _{n=1}^\infty a_n$ be a convergent series of positive real numbers. L. Olivier proved that if the sequence $(a_n)$ is non-increasing, then $\lim \limits _{n \to \infty } n a_n = 0$. In the present paper: \endgraf (a) We formulate and prove a necessary and sufficient condition for having $\lim \limits _{n \to \infty } n a_n = 0$; Olivier's theorem is a consequence of our Theorem \ref {import}. \endgraf (b) We prove properties analogous to Olivier's property when the usual convergence is replaced by the $\mathcal I$-convergence, that is a convergence according to an ideal $\mathcal I$ of subsets of $\mathbb N$. Again, Olivier's theorem is a consequence of our Theorem \ref {Iol}, when one takes as $\mathcal I$ the ideal of all finite subsets of $\mathbb N$. (English) |
Keyword:
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convergent series |
Keyword:
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Olivier's theorem |
Keyword:
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ideal |
Keyword:
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$\mathcal {I}$-convergence |
Keyword:
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$\mathcal {I}$-monotonicity |
MSC:
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11B05 |
MSC:
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40A05 |
MSC:
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40A35 |
idZBL:
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Zbl 06674858 |
idMR:
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MR3576795 |
DOI:
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10.21136/MB.2016.0057-15 |
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Date available:
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2017-01-03T15:17:08Z |
Last updated:
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2020-07-01 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/145956 |
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Reference:
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[1] Bandyopadhyay, S.: Mathematical Analysis: Problems and Solutions.Academic Publishers, Kolkata (2006). |
Reference:
|
[2] Knopp, K.: Theory and Applications of Infinite Series.Springer, Berlin (1996), German. Zbl 0842.40001 |
Reference:
|
[3] Kostyrko, P., Šalát, T., Wilczyński, W.: $\scr I$-convergence.Real Anal. Exch. 26 (2001), 669-685. MR 1844385 |
Reference:
|
[4] Krzyž, J.: Olivier's theorem and its generalizations.Pr. Mat. 2 (1956), Polish, Russian 159-164. Zbl 0075.25802, MR 0084609 |
Reference:
|
[5] Olivier, L.: Remarks on infinite series and their convergence.J. Reine Angew. Math. 2 (1827), French 31-44. MR 1577632 |
Reference:
|
[6] Šalát, T., Toma, V.: A classical Olivier's theorem and statistical convergence.Ann. Math. Blaise Pascal 10 (2003), 305-313. Zbl 1061.40001, MR 2031274, 10.5802/ambp.179 |
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