Volume 2018 Issue 1

Author(s): M. C. Mahesh Kumar\(^1\)1,2, H. M. Nagesh1,2
1Department of Mathematics, Government First Grade College, K. R. Puram, Bangalore 560 036, India.; (M.C.M.K)
2Department of Science and Humanities, PES University-Electronic City Campus, Hosur Road (1 km before Electronic City), Bangalore-560 100, India.; (H.M.N)
Abstract:

For an arborescence \(A_r\), a directed pathos total digraph \(Q=DPT(A_r)\) has vertex set \(V(Q)=V(A_r)\cup A(A_r)\cup P(A_r)\), = where \(V(A_r)\) is the vertex set, \(A(A_r)\) is the arc set, and \(P(A_r)\) is a directed pathos set of \(A_r\). The arc set \(A(Q)\) consists of the following arcs: \(ab\) such that \(a,b \in A(A_r)\) and the head of \(a\) coincides with the tail of \(b\); \(uv\) such that \(u,v \in V(A_r)\) and \(u\) is adjacent to \(v\); \(au\) \((ua)\) such that \(a\in A(A_r)\) and \(u \in V(A_r)\) and the head (tail) of \(a\) is \(u\); \(Pa\) such that \(a \in A(A_r)\) and \(P \in P(A_r)\) and the arc \(a\) lies on the directed path \(P\); \(P_iP_j\) such that \(P_i, P_j \in P(A_r)\) and it is possible to reach the head of \(P_j\) from the tail of \(P_i\) through a common vertex, but it is possible to reach the head of \(P_i\) from the tail of \(P_j\). For this class of digraphs we discuss the planarity; outerplanarity; maximal outerplanarity; minimally nonouterplanarity; and crossing number one properties of these digraphs. The problem of reconstructing an arborescence from its directed pathos total digraph is also presented.

Author(s): Muhammad Imran1,2, Asima Asghar1,2, Abdul Qudair Baig1,2
1Department of Mathematical Sciences, United Arab Emirates University, Al Ain, P.O. Box 15551, UAE.; (M.I)
2Department of Mathematics, The University of Lahore, Pakpattan Campus, Pakpattan 57400, Pakistan.; (A.A & A.Q.B)
Abstract:

The application of graph theory in chemical and molecular structure research far exceeds people’s expectations, and it has recently grown exponentially. In the molecular graph, atoms are represented by vertices and bonded by edges. In this report, we study the several Zagreb polynomials and Redefined Zagreb indices of Oxide Network.

Author(s): Wei Gao1, Asima Asghar2, Waqas Nazeer3
1School of Information Science and Technology, Yunnan Normal University, Kunming 650500, China.
2Department of Mathematics, The University of Lahore, Pakpattan Campus, Pakpattan 57400, Pakistan.
3Division of Science and Technology, University of Education, Lahore 54000, Pakistan.
Abstract:

Topological indices are numerical numbers associated with a graph that helps to predict many properties of underlined graph. In this paper we aim to compute multiplicative degree based topological indices of Jahangir graph.

Author(s): Kwara Nantomah1
1Department of Mathematics, Faculty of Mathematical Sciences, University for Development Studies, Navrongo Campus, P. O. Box 24, Navrongo, UE/R, Ghana; (K.N)
Abstract:

In this paper, we study completete monotonicity properties of certain functions associated with the polygamma functions. Subsequently, we deduce some inequalities involving difference of polygamma functions.

Author(s): Rachanna Kanabur1, Sunilkumar Hosamani2
1Department of Mathematics, Bldea’s Commerce BHS Arts and TGP Science, College, Jamakhandi – 587301 Karnataka, India
2Department of Mathematics, Rani Channamma University Belagavi – 591156 Karnataka, India
Abstract:

A carbon nanotube (CNT) is a miniature cylindrical carbon structure that has hexagonal graphite molecules attached at the edges. In this paper, we compute the numerical invariant (Topological indices) of linear [n]-phenylenic, lattice of \(C_{4}C_{6}C_{8}[m, n]\), \(TUC_{4}C_{6}C_{8}[m, n]\) nanotube, \(C_{4}C_{6}C_{8}[m, n]\) nanotori.