Results 41 to 50 of about 532 (122)
On the inducibility of small trees [PDF]
Discrete Mathematics & Theoretical Computer Science, 2019 The quantity that captures the asymptotic value of the maximum number of appearances of a given topological tree (a rooted tree with no vertices of outdegree $1$) $S$ with $k$ leaves in an arbitrary tree with sufficiently large number of leaves is called
Audace A. V. Dossou-Olory +1 more
doaj +1 more source
Making multigraphs simple by a sequence of double edge swaps
, 2021 We show that any loopy multigraph with a graphical degree sequence can be transformed into a simple graph by a finite sequence of double edge swaps with each swap involving at least one loop or multiple edge.
Sjöstrand, Jonas
core
Contraharmonic Index: Extremal Results for Unicyclic Graphs and Bounds for General Graphs
Journal of Mathematics, Volume 2026, Issue 1, 2026.Let G be a graph with edge set E(G). The degree of a vertex w in G is denoted by dw. The contraharmonic index of G is defined as CHG=∑uv∈EGdu+dv−1du2+dv2. In this paper, we investigate several properties of the contraharmonic index, including extremal results for unicyclic graphs of a given order, as well as bounds and the effects of an edge removal in
Abdulaziz Mutlaq Alotaibi +2 more
wiley +1 more source
ON TOPOLOGICAL PROPERTIES OF PLANE GRAPHS BY USING LINE OPERATOR ON THEIR SUBDIVISIONS
International Journal of Apllied Mathematics, 2018 In this paper, we will compute some topological indices such as Zagreb indices M1(G), M2(G), M3(G), Zagreb coindices M1(G), M1(G), M2(G), M2(G)), M2(G), hyper-Zagreb index HM(G), atom-bond connectivity index ABC(G), sum connectivity index χ(G ...
Mohamad Nazri Husin +4 more
semanticscholar +1 more source
On the Clean Graph of Commutative Artinian Rings
International Journal of Mathematics and Mathematical Sciences, Volume 2025, Issue 1, 2025.For a commutative Artinian ring R with unity, the clean graph Cl(R) is a graph with vertices in the form of an ordered pair (e, u), where e is an idempotent and u is a unit of ring R, respectively. Two distinct vertices (e, u) and (f, v) are adjacent in Cl(R) if and only if ef = fe = 0 or uv = vu = 1.
R. Singh +3 more
wiley +1 more source
Degree Subtraction Adjacency Eigenvalues and Energy of Graphs Obtained From Regular Graphs
Open Journal of Discrete Applied Mathematics, 2018 Let V (G) = {v1, v2, . . . , vn} be the vertex set of G and let dG(vi) be the degree of a vertex vi in G. The degree subtraction adjacency matrix of G is a square matrix DSA(G) = [dij ], in which dij = dG(vi) − dG(vj), if vi is adjacent to vj and dij = 0,
H. Ramane, Hemaraddi N. Maraddi
semanticscholar +1 more source
Trees with the most subtrees -- an algorithmic approach
, 2012 When considering the number of subtrees of trees, the extremal structures which maximize this number among binary trees and trees with a given maximum degree lead to some interesting facts that correlate to other graphical indices in applications.
Gray, Daniel +3 more
core +1 more source
On General Sum‐Connectivity Index and Number of Segments of Fixed‐Order Chemical Trees
Journal of Mathematics, Volume 2025, Issue 1, 2025.Nowadays, one of the most active areas in mathematical chemistry is the study of the mathematical characteristics associated with molecular descriptors. The primary objective of the current study is to find the largest value of χα of graphs in the class of all fixed‐order chemical trees with a particular number of segments for α > 1, where χα is the ...
Muzamil Hanif +5 more
wiley +1 more source
On First Hermitian-Zagreb Matrix and Hermitian-Zagreb Energy
International Journal of Scientific Research in Mathematical and Statistical Sciences, 2018 A mixed graph is a graph with edges and arcs, which can be considered as a combination of an undirected graph and a directed graph. In this paper we propose a Hermitian matrix for mixed graphs which is a modified version of the classical adjacency matrix
A. Bharali
semanticscholar +1 more source
A Tur\'an-type problem on degree sequence [PDF]
, 2013 Given $p\geq 0$ and a graph $G$ whose degree sequence is $d_1,d_2,\ldots,d_n$, let $e_p(G)=\sum_{i=1}^n d_i^p$. Caro and Yuster introduced a Tur\'an-type problem for $e_p(G)$: given $p\geq 0$, how large can $e_p(G)$ be if $G$ has no subgraph of a ...
Li, Xueliang, Shi, Yongtang
core