Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures)Khayyam Journal of Mathematics2423-47884120180101Local Convergence for a Family of Sixth Order Chebyshev-Halley-Type Methods in Banach Space Under Weak Conditions1125187310.22034/kjm.2017.51873ENIoannis K.ArgyrosDepartment of Mathematical Sciences, Cameron University, Lawton, OK
73505, USA.0000-0002-9189-9298Santhosh GeorgeDepartment of Mathematical and Computational Sciences, National Institute of Technology Karnataka, India-575 025.0000-0002-3530-5539Journal Article20170706We present a local convergence analysis for a family of super-Halley methods of high convergence order in order to approximate a solution of a nonlinear equation in a Banach space. Our sufficient convergence conditions involve only hypotheses on the first and second <span>Fréchet</span>-derivative of the operator involved. Earlier studies use hypotheses up to the third <span>Fréchet-</span>derivative. Numerical examples are also provided in this study.https://www.kjm-math.org/article_51873_01211642c310828d7695de3477fc151d.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures)Khayyam Journal of Mathematics2423-47884120180101The Second Symmetric Product of Finite Graphs from a Homotopical Viewpoint13275343210.22034/kjm.2017.53432ENJosé G. AnayaFacultad de Ciencias, Universidad Autónoma del Estado de México, Instituto
Literario No. 100, Col. Centro, C. P. 50000, Toluca, México.Alfredo CanoFacultad de Ciencias, Universidad Autónoma del Estado de México, Instituto
Literario No. 100, Col. Centro, C. P. 50000, Toluca, México.Enrique Castañeda-AlvaradoFacultad de Ciencias, Universidad Autónoma del Estado de México, Instituto
Literario No. 100, Col. Centro, C. P. 50000, Toluca, México.0000-0002-4393-2348Marco A. Castillo-RubíFacultad de Ciencias, Universidad Autónoma del Estado de México, Instituto
Literario No. 100, Col. Centro, C. P. 50000, Toluca, México.Journal Article20170905This paper describes the classification of the $n$-fold symmetric product of a finite graph by means of its homotopy type, having as universal models the $n$-fold symmetric product of the wedge of $n$-circles; and introduces a CW-complex called $binomial\ torus$, which is homeomorphic to a space that is a strong deformation retract of the second symmetric products of the wedge of $n$-circles. Applying the above we calculate the fundamental group, Euler characteristic, homology and cohomology groups of the second symmetric product of finite graphs.https://www.kjm-math.org/article_53432_e889f317edc114515e2bb1d54c2de580.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures)Khayyam Journal of Mathematics2423-47884120180101A Subclass of Harmonic Univalent Functions Defined by Means of Differential Subordination28385365510.22034/kjm.2017.53655ENSerkan ÇakmakDepartment of Mathematics, Faculty of Arts and Science, Uludag University, 16059, Görükle, Bursa, Turkey.Sibel YalçınDepartment of Mathematics, Faculty of Arts and Science, Uludag University, 16059, Görükle, Bursa, Turkey.0000-0002-0243-8263Şahsene AltinkayaDepartment of Mathematics, Faculty of Arts and Science, Uludag University, 16059, Görükle, Bursa, Turkey.Journal Article20171030The aim of this paper is to introduce a new class of harmonic functions<br />defined by use of a subordination. We find necessary and sufficient<br />conditions, radii of starlikeness and convexity and compactness for this<br />class of functions. Moreover, by using extreme points theory we also obtain<br />coefficients estimates, distortion theorems for this class of functions. On<br />the other hand, some results (corollaries) on the paper are pointed out.https://www.kjm-math.org/article_53655_37704e2531cb2f56dc09561deff132ef.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures)Khayyam Journal of Mathematics2423-47884120180101Ostrowski Type Fractional Integral Operators for Generalized Beta $(r,g)$-Preinvex Functions39585468010.22034/kjm.2017.54680ENArtion KashuriDepartment of Mathematics, Faculty of Technical Science, University ”Ismail
Qemali”, Vlora, Albania.0000-0003-0115-3079Rozana LikoDepartment of Mathematics, Faculty of Technical Science, University ”Ismail
Qemali”, Vlora, Albania.0000-0003-2439-8538Tingsong DuCollege of Science, China Three Gorges University, 443002, Yichang, P. R.
China.Journal Article20170606In the present paper, the notion of generalized beta $(r,g)$-preinvex function is applied for establish some new generalizations of Ostrowski type inequalities via fractional integral operators. These results not only extend the results appeared in the literature [43] but also provide new estimates on these type. At the end, some applications to special means are given.https://www.kjm-math.org/article_54680_ff16555c24403f6b3496ce50c6fd8bbf.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures)Khayyam Journal of Mathematics2423-47884120180101Constructing an Element of a Banach Space with Given Deviation from its Nested Subspaces59765515810.22034/kjm.2018.55158ENAsuman AksoyDepartment of Mathematics, Claremont McKenna College, 850 Columbia Avenue, Claremont, CA 91711, USA.Qidi PengInstitute of Mathematical Sciences, Claremont Graduate University, 710 N.
College Avenue, Claremont, CA 91711, USA.Journal Article20171215This paper contains two improvements on a theorem of S. N. Bernstein for Banach spaces. We show that if $X$ is an arbitrary infinite-dimensional Banach space, $\{Y_n\}$ is a sequence of strictly nested subspaces of $ X$ and if $\{d_n\}$ is a non-increasing sequence of non-negative numbers tending to 0, then for any $c\in(0,1]$<br /> we can find $x_{c} \in X$, such that the distance $\rho(x_{c}, Y_n)$ from $x_{c}$ to $Y_n$ satisfies<br />$$<br />c d_n \leq \rho(x_{c},Y_n) \leq 4c d_n,~\mbox{for all $n\in\mathbb N$}.<br />$$<br />We prove the above inequality by first improving Borodin (2006)'s result for Banach spaces by weakening his condition on the sequence $\{d_n\}$. The weakened condition on $d_n$ requires refinement of Borodin's construction to extract an element in $X$, whose distances from the nested subspaces are precisely the given values $d_n$.https://www.kjm-math.org/article_55158_6967a156928a4b5003d50eae0fedc911.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures)Khayyam Journal of Mathematics2423-47884120180101Laplacian and Signless Laplacian Spectrum of Commuting Graphs of Finite Groups77875749010.22034/kjm.2018.57490ENJutirekha DuttaDepartment of Mathematical Sciences, Tezpur University, Napaam-784028,
Sonitpur, Assam, India.Rajat KantiNathDepartment of Mathematical Sciences, Tezpur University, Napaam-784028,
Sonitpur, Assam, India.Journal Article20171214The commuting graph of a finite non-abelian group $G$ with center $Z(G)$, denoted by $\Gamma_G$, is a simple undirected graph whose vertex set is $G\setminus Z(G)$, and two distinct vertices $x$ and $y$ are adjacent if and only if $xy = yx$.<br />A finite non-abelian group $G$ is called super integral if the spectrum, Laplacian spectrum and signless Laplacian spectrum of its commuting graph contain only integers.<br />In this paper, we first compute Laplacian spectrum and signless Laplacian spectrum of several families of finite non-abelian groups and conclude that those groups are super integral. As an application of our results we obtain<br />some positive rational numbers $r$ such that $G$ is super integral if commutativity degree of $G$ is $r$. In the last section, we show that $G$ is super integral if $G$ is not isomorphic to $S_4$ and its commuting graph is planar. We conclude the paper showing that $G$ is super integral if its commuting graph is toroidal.https://www.kjm-math.org/article_57490_293c3a034fe521dab3aecbbd7b850f8f.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures)Khayyam Journal of Mathematics2423-47884120180101Polynomial Bounds for a Class of Univalent Function Involving Sigmoid Function881015772110.22034/kjm.2018.57721ENOlubunmi A.Fadipe-JosephDepartment of Mathematics, University of Ilorin, P.M.B. 1515 Ilorin,
Nigeria.0000-0001-7781-6807Bilikis B.KadirDepartment of Mathematics, University of Ilorin, P.M.B. 1515 Ilorin,
Nigeria.Sunday E.AkinwumiDepartment of Mathematics, University of Ilorin, P.M.B. 1515 Ilorin,
Nigeria.Esther O.AdeniranDepartment of Mathematics, University of Ilorin, P.M.B. 1515 Ilorin,
Nigeria.Journal Article20180919In this work, a new subclass of univalent function was defined using the <span>Sălăgean</span> differential operator involving the modified sigmoid function and the Chebyshev polynomials. The coefficient bounds and the Fekete-Szego functional of this class were obtained using subordination principle. The results obtained agree and extend some earlier results.https://www.kjm-math.org/article_57721_db05732ca68e42ed7238c4b1cd3b3338.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures)Khayyam Journal of Mathematics2423-47884120180101Ricci Solitons on Kenmotsu Manifolds under $D$-Homothetic Deformation1021095772510.22034/kjm.2018.57725ENHalammanavar G.NagarajaDepartment of Mathematics, Jnanabharathi Campus, Bangalore University,
Bengaluru, 560 056, INDIA.Devasandra L.Kiran KumarDepartment of Mathematics, Jnanabharathi Campus, Bangalore University,
Bengaluru, 560 056, INDIA.Venkateshmurthy S.PrasadDepartment of Mathematics, Regional institute of Education (NCERT), Manasagangotri, Mysore, 570006, INDIA.Journal Article20171117The aim of the present paper is to study Ricci solitons in Kenmotsu manifolds under $D$-homothetic deformation. We analyzed behaviour of Ricci solitons when potential vector field is orthogonal to Reeb vector field and pointwise collinear with Reeb vector field. Further we prove Ricci solitons in $D$-homothetically transformed Kenmotsu manifolds are shrinking.https://www.kjm-math.org/article_57725_899a6e6b876f185709cce8565826c41a.pdf