Volume 2021 Issue 3

Author(s): Özge Çolakoglu Havare1
1Mersin University, Science and Arts Faculty, Mathematics Department, 33343, Mersin-Turkey
Abstract:

The inverse sum indeg index \(ISI(G)\) of a graph is equal to the sum over all edges \(uv\in E(G)\) of weights \(\frac{d_{u}d_{v}}{d_{u}+d_{v}}\). In this paper, we calculated the inverse indeg indices and inverse indeg energies that give information about the physicochemical properties and biological characteristics of Hyaluronic Acid-Paclitaxel conjugates used in the production of drugs used in the treatment of cancer disease. This study presents the relation between the ISI index and the ISI energy of the molecular graph of Hyaluronic Acid-Paclitaxel conjugates.

Author(s): Xiaojing Wang1, Zhen Lin2, Lianying Miao1
1School of Mathematics, China University of Mining and Technology, Xuzhou, 221116, Jiangsu, P.R. China.
2School of Mathematics and Statistics, Qinghai Normal University, Xining, 810008, Qinghai, P.R. China.
Abstract:

In this paper, we obtain the quantitative calculation formula of the degree-based topological indices of four standard product for the path and regular graphs, which unify to solve the question on product of these basic graphs without having to deal with it one by one separately. As applications, we give corresponding calculation formula of the general Randić index, the first general Zagreb index and the general sum-connectivity index.

Author(s): Benedikt Valentin Meylahn1, Jan Harm van Vuuren1
1Stellenbosch Unit for Operations Research in Engineering, Department of Industrial Engineering, Stellenbosch University, Stellenbosch, South Africa.
Abstract:

The temporal dynamics of games have been studied widely in evolutionary spatial game theory using simulation. Each player is usually represented by a vertex of a graph and plays a particular game against every adjacent player independently. These games result in payoffs to the players which affect their relative fitness. The fitness of a player, in turn, affects its ability to reproduce. In this paper, we analyse the temporal dynamics of the evolutionary 2-person, 2-strategy snowdrift game in which players are arranged along a cycle of arbitrary length. In this game, each player has the option of adopting one of two strategies, namely cooperation or defection, during each game round. We compute the probability of retaining persistent cooperation over time from a random initial assignment of strategies to players. We also establish bounds on the probability that a small number of players of a particular mutant strategy introduced randomly into a cycle of players which have established the opposite strategy leads to the situation where all players eventually adopt the mutant strategy. We adopt an analytic approach throughout as opposed to a simulation approach clarifying the underlying dynamics intrinsic to the entire class of evolutionary spatial snowdrift games.

Author(s): Gowtham Kalkere Jayanna1, Ivan Gutman2
1Department of Mathematics, University College of Science, Tumkur University, Tumakuru, India.
2Faculty of Science, University of Kragujevac, 34000 Kragujevac, Serbia.
Abstract:

Let \(G\) be a simple graph with vertex set \(V=\{v_1,v_2,\ldots,v_n \}\), and let \(d_i\) be the degree of the vertex \(v_i\). The Sombor matrix of \(G\) is the square matrix \(\mathbf A_{SO}\) of order \(n\), whose \((i,j)\)-element is \(\sqrt{d_i^2+d_j^2}\) if \(v_i\) and \(v_j\) are adjacent, and zero otherwise. We study the characteristic polynomial, spectrum, and energy of \(\mathbf A_{SO}\). A few results for the coefficients of the characteristic polynomial, and bounds for the energy of \(\mathbf A_{SO}\) are established.

Author(s): Johan Kok1
1Independent Mathematics Researcher, City of Tshwane, South Africa & Visiting Faculty at CHRIST (Deemed to be a University), Bangalore, India.
Abstract:

This note presents the characterization of the families of star, helm, flower and complete graphs by total vertex stress. The note does not present results for many families of graphs but, it highlights important philosophical (math. phil.) aspects for further research. In particular the novelty concepts of forgiven contradictions denoted by, iff\(_f\) as well as iffness and \(f\)-statements are introduced. The author suggests that the characterization of other families of graphs by total vertex stress is possible.

Author(s): I. Silambarasan1
1Department of Mathematics, Sri Manakula Vinayagar Engineering College, Madagadipet, Puducherry-605107, India.
Abstract:

In this paper, we define some new operators \([(A \$ B),(A \# B),(A\ast B),(A \rightarrow B) ]\) of Fermatean fuzzy matrices and investigate their algebraic properties. Further, the necessity and possibility operators of Fermatean fuzzy matrices are proved. Finally, we have identified and proved several of these properties, particularly those involving the operator \(A\rightarrow B\) defined as Fermatean fuzzy implication with other operators.

Author(s): Rasul Rasuli1
1Department of Mathematics, Payame Noor University (PNU), Tehran, Iran.
Abstract:

In this paper, by using \(S\)-norms, we defined anti fuzzy subgroups and anti fuzzy normal subgroups which are new notions and considered their fundamental properties and also made an attempt to study the characterizations of them. Next we investigated image and pre image of them under group homomorphisms. Finally, we introduced the direct sum of them and proved that direct sum of any family of them is also anti fuzzy subgroups and anti fuzzy normal subgroups under \(S\)-norms, respectively.