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            <front>

                <journal-meta>
                                    <journal-id></journal-id>
            <journal-title-group>
                                                                                    <journal-title>Hacettepe Journal of Mathematics and Statistics</journal-title>
            </journal-title-group>
                            <issn pub-type="ppub">2651-477X</issn>
                                        <issn pub-type="epub">2651-477X</issn>
                                                                                            <publisher>
                    <publisher-name>Hacettepe University</publisher-name>
                </publisher>
                    </journal-meta>
                <article-meta>
                                        <article-id/>
                                                                <article-categories>
                                            <subj-group  xml:lang="en">
                                                            <subject>Mathematical Sciences</subject>
                                                    </subj-group>
                                            <subj-group  xml:lang="tr">
                                                            <subject>Matematik</subject>
                                                    </subj-group>
                                    </article-categories>
                                                                                                                                                        <title-group>
                                                                                                                                                            <article-title>On regular bipartite divisor graph for the set of irreducible character degrees</article-title>
                                                                                                    </title-group>
            
                                                    <contrib-group content-type="authors">
                                                                        <contrib contrib-type="author">
                                                                    <contrib-id contrib-id-type="orcid">
                                        https://orcid.org/0000-0001-6486-7736</contrib-id>
                                                                <name>
                                    <surname>Hafezieh</surname>
                                    <given-names>Roghayeh</given-names>
                                </name>
                                                                    <aff>GEBZE TECHNICAL UNIVERSITY</aff>
                                                            </contrib>
                                                                                </contrib-group>
                        
                                        <pub-date pub-type="pub" iso-8601-date="20191208">
                    <day>12</day>
                    <month>08</month>
                    <year>2019</year>
                </pub-date>
                                        <volume>48</volume>
                                        <issue>6</issue>
                                        <fpage>1620</fpage>
                                        <lpage>1625</lpage>
                        
                        <history>
                                    <date date-type="received" iso-8601-date="20180114">
                        <day>01</day>
                        <month>14</month>
                        <year>2018</year>
                    </date>
                                                    <date date-type="accepted" iso-8601-date="20180518">
                        <day>05</day>
                        <month>18</month>
                        <year>2018</year>
                    </date>
                            </history>
                                        <permissions>
                    <copyright-statement>Copyright © 2002, Hacettepe Journal of Mathematics and Statistics</copyright-statement>
                    <copyright-year>2002</copyright-year>
                    <copyright-holder>Hacettepe Journal of Mathematics and Statistics</copyright-holder>
                </permissions>
            
                                                                                                                        <abstract><p>Given a finite group $G$, the \textit{bipartite divisor graph}, denoted by $B(G)$, for its irreducible character degrees is the bipartite graph with bipartition consisting of $cd(G)^{*}$, where $cd(G)^{*}$ denotes the nonidentity irreducible character degrees of $G$ and the $\rho(G)$ which is the set of prime numbers that divide these degrees, and with $\{p,n\}$  being an edge if $\gcd(p,n)\neq 1$. In [Bipartite divisor graph for the set of irreducible character degress, Int. J. Group Theory, 2017], the author considered the cases where $B(G)$ is a path or a cycle and discussed some properties of $G$. In particular she proved that $B(G)$ is a cycle if and only if $G$ is solvable and $B(G)$ is either a cycle of length four or six. Inspired by $2$-regularity of cycles, in this paper we consider the case where $B(G)$ is an $n$-regular graph for $n\in\{1,2,3\}$. In particular we prove that there is no solvable group whose bipartite divisor graph is $C_{4}+C_{6}$.</p></abstract>
                                                            
            
                                                                                        <kwd-group>
                                                    <kwd>bipartite divisor graph</kwd>
                                                    <kwd>  irreducible character degrees</kwd>
                                                    <kwd>  regular graph</kwd>
                                            </kwd-group>
                            
                                                                                                                                                    </article-meta>
    </front>
    <back>
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                    </back>
    </article>
