Results 51 to 60 of about 140 (88)

Strong Geodetic Problem in Networks

Discussiones Mathematicae Graph Theory, 2020
In order to model certain social network problems, the strong geodetic problem and its related invariant, the strong geodetic number, are introduced.
Manuel Paul, Klavžar Sandi, Xavier Antony, Arokiaraj Andrew, Thomas Elizabeth   +4 more
doaj   +1 more source

Inverse Problem on the Steiner Wiener Index

Discussiones Mathematicae Graph Theory, 2018
The Wiener index W(G) of a connected graph G, introduced by Wiener in 1947, is defined as W(G) =∑u,v∈V (G)dG(u, v), where dG(u, v) is the distance (the length a shortest path) between the vertices u and v in G. For S ⊆ V (G), the Steiner distance d(S) of
Li Xueliang, Mao Yaping, Gutman Ivan
doaj   +1 more source

A New Transport Distance and Its Associated Ricci Curvature of Hypergraphs

Analysis and Geometry in Metric Spaces, 2022
The coarse Ricci curvature of graphs introduced by Ollivier as well as its modification by Lin–Lu– Yau have been studied from various aspects. In this paper, we propose a new transport distance appropriate for hypergraphs and study a generalization of ...
Akamatsu Tomoya
doaj   +1 more source

Antipodal graphs and digraphs

, 1991
International Journal of Mathematics and Mathematical Sciences, Volume 16, Issue 3, Page 579-586, 1993.
Garry Johns, Karen Sleno
wiley   +1 more source

Sharp bounds for partition dimension of generalized Möbius ladders

Open Mathematics, 2018
The concept of minimal resolving partition and resolving set plays a pivotal role in diverse areas such as robot navigation, networking, optimization, mastermind games and coin weighing.
Hussain Zafar, Khan Junaid Alam, Munir Mobeen, Saleem Muhammad Shoaib, Iqbal Zaffar   +4 more
doaj   +1 more source

A Survey on Packing Colorings

Discussiones Mathematicae Graph Theory, 2020
If S = (a1, a2, . . .) is a non-decreasing sequence of positive integers, then an S-packing coloring of a graph G is a partition of V (G) into sets X1, X2, . . .
Brešar Boštjan, Ferme Jasmina, Klavžar Sandi, Rall Douglas F.   +3 more
doaj   +1 more source

Four-point condition matrices of edge-weighted trees

Special Matrices
Formulas for the determinant of distance matrix DT{D}_{T} of tree TT are known in the unweighted case and in the case when the edges of TT have commuting variable weights. Associated with the four-point condition (4PC) and a tree TT are two matrices, the
Azimi Ali, Jana Rakesh, Nagar Mukesh K., Sivasubramanian Sivaramakrishnan   +3 more
doaj   +1 more source

A Characterization for 2-Self-Centered Graphs

Discussiones Mathematicae Graph Theory, 2018
A graph is called 2-self-centered if its diameter and radius both equal to 2. In this paper, we begin characterizing these graphs by characterizing edge-maximal 2-self-centered graphs via their complements.
Shekarriz Mohammad Hadi, Mirzavaziri Madjid, Mirzavaziri Kamyar   +2 more
doaj   +1 more source

Bounds on F-index of tricyclic graphs with fixed pendant vertices

Open Mathematics, 2020
The F-index F(G) of a graph G is obtained by the sum of cubes of the degrees of all the vertices in G. It is defined in the same paper of 1972 where the first and second Zagreb indices are introduced to study the structure-dependency of total π-electron ...
Akram Sana, Javaid Muhammad, Jamal Muhammad   +2 more
doaj   +1 more source

The Second Neighbourhood for Bipartite Tournaments

Discussiones Mathematicae Graph Theory, 2019
Let T (X ∪ Y, A) be a bipartite tournament with partite sets X, Y and arc set A. For any vertex x ∈ X ∪Y, the second out-neighbourhood N++(x) of x is the set of all vertices with distance 2 from x.
Li Ruijuan, Sheng Bin
doaj   +1 more source