Results 21 to 30 of about 262 (120)
On Incidence Coloring of Complete Multipartite and Semicubic Bipartite Graphs
Discussiones Mathematicae Graph Theory, 2018 In the paper, we show that the incidence chromatic number χi of a complete k-partite graph is at most Δ + 2 (i.e., proving the incidence coloring conjecture for these graphs) and it is equal to Δ + 1 if and only if the smallest part has only one vertex ...
Janczewski Robert +2 more
doaj +1 more source
On the number of perfect matchings in random polygonal chains
Open Mathematics, 2023 Let GG be a graph. A perfect matching of GG is a regular spanning subgraph of degree one. Enumeration of perfect matchings of a (molecule) graph is interest in chemistry, physics, and mathematics.
Wei Shouliu +3 more
doaj +1 more source
On the Harary index of graph operations
, 2013 The Harary index is defined as the sum of reciprocals of distances between all pairs of vertices of a connected graph. In this paper, expressions for the Harary indices of the join, corona product, Cartesian product, composition and disjunction of graphs
K. Das +4 more
semanticscholar +1 more source
The bipartite Laplacian matrix of a nonsingular tree
Special Matrices, 2023 For a bipartite graph, the complete adjacency matrix is not necessary to display its adjacency information. In 1985, Godsil used a smaller size matrix to represent this, known as the bipartite adjacency matrix.
Bapat Ravindra B. +2 more
doaj +1 more source
The Arithmetic Tutte polynomial of two matrices associated to Trees
Special Matrices, 2018 Arithmetic matroids arising from a list A of integral vectors in Zn are of recent interest and the arithmetic Tutte polynomial MA(x, y) of A is a fundamental invariant with deep connections to several areas. In this work, we consider two lists of vectors
Bapat R. B. +1 more
doaj +1 more source
Banhatti, revan and hyper-indices of silicon carbide Si2C3-III[n,m]
Open Chemistry, 2021 In recent years, several structure-based properties of the molecular graphs are understood through the chemical graph theory. The molecular graph GG of a molecule consists of vertices and edges, where vertices represent the atoms in a molecule and edges ...
Zhao Dongming +6 more
doaj +1 more source
Special Matrices, 2019 Considered are combinatorially symmetric matrices, whose graph is a given tree, in view of the fact recent analysis shows that the geometric multiplicity theory for the eigenvalues of such matrices closely parallels that for real symmetric (and complex ...
Saiago Carlos M.
doaj +1 more source
Total Roman {2}-Dominating Functions in Graphs
Discussiones Mathematicae Graph Theory, 2022 A Roman {2}-dominating function (R2F) is a function f : V → {0, 1, 2} with the property that for every vertex v ∈ V with f(v) = 0 there is a neighbor u of v with f(u) = 2, or there are two neighbors x, y of v with f(x) = f(y) = 1.
Ahangar H. Abdollahzadeh +3 more
doaj +1 more source
Structures of W(2.2) Lie conformal algebra
Open Mathematics, 2016 The purpose of this paper is to study W(2, 2) Lie conformal algebra, which has a free ℂ[∂]-basis {L, M} such that [LλL]=(∂+2λ)L,[LλM]=(∂+2λ)M,[MλM]=0$\begin{equation}[{L_\lambda }L] = (\partial + 2\lambda )L,[{L_\lambda }M] = (\partial + 2\lambda )M,[{M_\
Yuan Lamei, Wu Henan
doaj +1 more source
Special Matrices, 2019 Given a combinatorially symmetric matrix A whose graph is a tree T and its eigenvalues, edges in T can be classified in four categories, based upon the change in geometric multiplicity of a particular eigenvalue, when the edge is removed.
Toyonaga Kenji
doaj +1 more source