<?xml version="1.0" encoding="utf-8"?>
<journal>
<title>Mathematical Researches</title>
<title_fa>پژوهش های ریاضی</title_fa>
<short_title>mmr</short_title>
<subject>Basic Sciences</subject>
<web_url>http://mmr.khu.ac.ir</web_url>
<journal_hbi_system_id>1</journal_hbi_system_id>
<journal_hbi_system_user>admin</journal_hbi_system_user>
<journal_id_issn>2588-2546</journal_id_issn>
<journal_id_issn_online>2588-2554</journal_id_issn_online>
<journal_id_pii></journal_id_pii>
<journal_id_doi>10.61186/mmr</journal_id_doi>
<journal_id_iranmedex></journal_id_iranmedex>
<journal_id_magiran></journal_id_magiran>
<journal_id_sid></journal_id_sid>
<journal_id_nlai></journal_id_nlai>
<journal_id_science></journal_id_science>
<language>fa</language>
<pubdate>
	<type>jalali</type>
	<year>1399</year>
	<month>8</month>
	<day>1</day>
</pubdate>
<pubdate>
	<type>gregorian</type>
	<year>2020</year>
	<month>11</month>
	<day>1</day>
</pubdate>
<volume>6</volume>
<number>3</number>
<publish_type>online</publish_type>
<publish_edition>1</publish_edition>
<article_type>fulltext</article_type>
<articleset>
	<article>


	<language>fa</language>
	<article_id_doi></article_id_doi>
	<title_fa>تخمین دقیق ضرایب لگاریتمی رده‌ای خاص از توابع تحلیلی</title_fa>
	<title>Sharp Estimates of Logarithmic Coefficients of Certain Class of Analytic Functions</title>
	<subject_fa>جبر</subject_fa>
	<subject>alg</subject>
	<content_type_fa>علمی پژوهشی بنیادی</content_type_fa>
	<content_type>S</content_type>
	<abstract_fa>فرض&amp;shy; کنید ردۀ همۀ توابع تحلیلی و نرمال&amp;shy; شده در قرص واحد باشد. برای هر تابع &amp;nbsp;از خانواۀ &amp;nbsp;ضرایب لگاریتمی &amp;nbsp;به&amp;shy; صورت زیر تعریف می&amp;shy;شوند: &lt;div style=&quot;text-align: center;&quot;&gt;&lt;/div&gt;&lt;br&gt;
هم&amp;shy;چنین، زیرردۀ &amp;nbsp;از &amp;nbsp;را به&amp;shy;صورت زیر تعریف می&amp;shy;کنیم&lt;br&gt;
&lt;br&gt;
که در آن &amp;quot; &amp;quot; رابطۀ تبعیت است. هدف ما در این مقاله تخمین دقیق نامساویها شامل ضرایب لگاریتمی برای توابعی است که به ردۀ &amp;nbsp; &amp;nbsp;تعلق دارند.&lt;br&gt;
&amp;nbsp;</abstract_fa>
	<abstract>&lt;strong&gt;Introduction&lt;/strong&gt;&lt;br&gt;
Let&amp;nbsp;&amp;nbsp;be the open unit disc in the complex plane&amp;nbsp;&amp;nbsp;and&amp;nbsp;&amp;nbsp;be the class of all functions of&amp;nbsp;&amp;nbsp;which are analytic and normalized in&amp;nbsp;&amp;nbsp;The subclass of&amp;nbsp;consisting of all univalent functions&amp;nbsp;&amp;nbsp;in&amp;nbsp;&amp;nbsp;is denoted by&amp;nbsp;&amp;nbsp;We say that a function&amp;nbsp;&amp;nbsp;is said to be starlike function if and only if for all We denote by&amp;nbsp;&amp;nbsp;the class of all satrlike functions in&amp;nbsp;If&amp;nbsp;&amp;nbsp;and&amp;nbsp;&amp;nbsp;are two of the functions in&amp;nbsp;&amp;nbsp;then we say that&amp;nbsp;&amp;nbsp;is subordinate to&amp;nbsp;&amp;nbsp;written&amp;nbsp;&amp;nbsp;or&amp;nbsp;&amp;nbsp;if there exists a Schwartz function&amp;nbsp;&amp;nbsp;such that&amp;nbsp;&amp;nbsp;for all&amp;nbsp;&amp;nbsp;Furthermore, if the function&amp;nbsp;&amp;nbsp;is univalent in&amp;nbsp;&amp;nbsp;then we have the following equivalence: Also for&amp;nbsp;and&amp;nbsp;&amp;nbsp;&amp;nbsp;their Hadamard product (or convolution) is defined by&amp;nbsp;The logarithmic coefficients&amp;nbsp;&amp;nbsp;&amp;nbsp;of&amp;nbsp;, denoted by&amp;nbsp;, are defined by These coefficients play an important role for various estimates in the theory of univalent functions. For example, consider the Koebe function where&amp;nbsp;&amp;nbsp;It is easy to see that the above function&amp;nbsp;&amp;nbsp;has logarithmic coefficients&amp;nbsp;where&amp;nbsp;&amp;nbsp;and&amp;nbsp;&amp;nbsp;Also for the function&amp;nbsp;&amp;nbsp;we have and&amp;nbsp;the sharp estimates&amp;nbsp;and&amp;nbsp;hold. We remark that the Fekete-Szego theorem is used. For&amp;nbsp;&amp;nbsp;, the problem seems much harder and no significant upper bounds for&amp;nbsp;&amp;nbsp;when&amp;nbsp;&amp;nbsp;appear to be known. Moreover, the problem of finding the sharp upper bound for&amp;nbsp;for&amp;nbsp;&amp;nbsp;is still open for&amp;nbsp;. The sharp upper bounds for modulus of logarithmic coefficients are known for functions in very few subclasses of&amp;nbsp;. For functions in the class&amp;nbsp;&amp;nbsp;it is easy to prove that&amp;nbsp;&amp;nbsp;for&amp;nbsp;&amp;nbsp;and the equality holds for the Koebe function. The celebrated de Branges&amp;#39; inequalities (the former Milin conjecture) for univalent functions&amp;nbsp;&amp;nbsp;state that where&amp;nbsp;&amp;nbsp;&amp;nbsp;with the equality if and only if De Branges used this inequality to prove the celebrated Bieberbach conjecture. Moreover, the de Branges&amp;#39; inequalities have also been the source of many other interesting inequalities involving logarithmic coefficients of&amp;nbsp;&amp;nbsp;such as&amp;nbsp;&amp;nbsp;&amp;nbsp; Let&amp;nbsp;&amp;nbsp;denote the class of functions&amp;nbsp;&amp;nbsp;and satisfying the following subordination relation where&amp;nbsp;.&lt;br&gt;
&lt;strong&gt;Material and methods&lt;/strong&gt;&lt;br&gt;
In this paper, first we obtain a subordination relation for the class&amp;nbsp;&amp;nbsp;and by making use of this relation we give two sharp estimates for the logarithmic coefficients of the function&amp;nbsp;&lt;br&gt;
&lt;strong&gt;Results and discussion&lt;/strong&gt;&lt;br&gt;
We obtain two sharp estimates for the logarithmic coefficients of the function&amp;nbsp;&lt;br&gt;
&lt;strong&gt;Conclusion&lt;/strong&gt;&lt;br&gt;
The following conclusions were drawn from this research.
&lt;ul&gt;
	&lt;li&gt;Logarithmic coefficients &amp;nbsp;of the function&amp;nbsp;&amp;nbsp;are estimated.&lt;/li&gt;
&lt;/ul&gt;
&lt;img alt=&quot;&quot; height=&quot;2&quot; src=&quot;file:///C:Users1AppDataLocalTempmsohtmlclip11clip_image001.gif&quot; width=&quot;267&quot; &gt;</abstract>
	<keyword_fa>تابع تک‌ارز, ستاره‌واری, تبعیت, ضرایب لگاریتمی, ضرب پیچشی</keyword_fa>
	<keyword>Univalent functions, Starlikeness, Subordination, Logarithmic coefficients, Hadamard product.</keyword>
	<start_page>441</start_page>
	<end_page>448</end_page>
	<web_url>http://mmr.khu.ac.ir/browse.php?a_code=A-10-552-1&amp;slc_lang=fa&amp;sid=1</web_url>


<author_list>
	<author>
	<first_name>Rahim</first_name>
	<middle_name></middle_name>
	<last_name>Kargar</last_name>
	<suffix></suffix>
	<first_name_fa>رحیم</first_name_fa>
	<middle_name_fa></middle_name_fa>
	<last_name_fa>کارگر</last_name_fa>
	<suffix_fa></suffix_fa>
	<email>rkargar1983@gmail.com</email>
	<code>10031947532846004040</code>
	<orcid>10031947532846004040</orcid>
	<coreauthor>No</coreauthor>
	<affiliation></affiliation>
	<affiliation_fa>سازمان مرکزی دانشگاه پیام نور، تهران</affiliation_fa>
	 </author>


	<author>
	<first_name>Ali</first_name>
	<middle_name></middle_name>
	<last_name>Ebadian</last_name>
	<suffix></suffix>
	<first_name_fa>علی</first_name_fa>
	<middle_name_fa></middle_name_fa>
	<last_name_fa>عبادیان</last_name_fa>
	<suffix_fa></suffix_fa>
	<email>a.ebadian@urmia.ac.ir</email>
	<code>10031947532846004041</code>
	<orcid>10031947532846004041</orcid>
	<coreauthor>No</coreauthor>
	<affiliation>Department of mathematics, Faculty of Science, Urmia University, Urmia, Iran.</affiliation>
	<affiliation_fa>دانشگاه ارومیه. دانشکده علوم. گروه ریاضی</affiliation_fa>
	 </author>


	<author>
	<first_name>Nader</first_name>
	<middle_name></middle_name>
	<last_name>Kanzi</last_name>
	<suffix></suffix>
	<first_name_fa>نادر</first_name_fa>
	<middle_name_fa></middle_name_fa>
	<last_name_fa>کنزی</last_name_fa>
	<suffix_fa></suffix_fa>
	<email>n.kanzi@pnu.ac.ir</email>
	<code>10031947532846004042</code>
	<orcid>10031947532846004042</orcid>
	<coreauthor>Yes
</coreauthor>
	<affiliation></affiliation>
	<affiliation_fa>سازمان مرکزی دانشگاه پیام نور، تهران</affiliation_fa>
	 </author>


</author_list>


	</article>
</articleset>
</journal>
