Results 61 to 70 of about 234 (95)

The Product Connectivity Banhatti Index of A Graph

open access: yesDiscussiones Mathematicae Graph Theory, 2019
Let G = (V, E) be a connected graph with vertex set V (G) and edge set E(G). The product connectivity Banhatti index of a graph G is defined as, PB(G)=∑ue1dG(u)dG(e)$PB(G) = \sum\nolimits_{ue} {{1 \over {\sqrt {{d_G}(u){d_G}(e)} }}}$ where ue means that ...
Kulli V.R.   +2 more
doaj   +1 more source

The Turań Number of 2P7

open access: yesDiscussiones Mathematicae Graph Theory, 2019
The Turán number of a graph H, denoted by ex(n, H), is the maximum number of edges in any graph on n vertices which does not contain H as a subgraph. Let Pk denote the path on k vertices and let mPk denote m disjoint copies of Pk.
Lan Yongxin, Qin Zhongmei, Shi Yongtang
doaj   +1 more source

Extremal Irregular Digraphs

open access: yesDiscussiones Mathematicae Graph Theory, 2018
A digraph is called irregular if its distinct vertices have distinct degree pairs. An irregular digraph is called minimal (maximal) if the removal of any arc (addition of any new arc) results in a non-irregular digraph. It is easily seen that the minimum
Górska Joanna   +4 more
doaj   +1 more source

Anti-Ramsey Number of Hanoi Graphs

open access: yesDiscussiones Mathematicae Graph Theory, 2019
Let ar(G,H) be the largest number of colors such that there exists an edge coloring of G with ar(G,H) colors such that each subgraph isomorphic to H has at least two edges in the same color. We call ar(G,H) the anti- Ramsey number for a pair of graphs (G,
Gorgol Izolda, Lechowska Anna
doaj   +1 more source

On Nordhaus-Gaddum type relations of δ-complement graphs. [PDF]

open access: yesHeliyon, 2023
Vichitkunakorn P   +2 more
europepmc   +1 more source

An efficient asymmetric removal lemma and its limitations

open access: yesForum of Mathematics, Sigma
The triangle removal states that if G contains $\varepsilon n^2$ edge-disjoint triangles, then G contains $\delta (\varepsilon )n^3$ triangles. Unfortunately, there are no sensible bounds on the order of growth of $\delta (\varepsilon )$
Lior Gishboliner   +2 more
doaj   +1 more source

Erdős-Gallai-Type Results for Total Monochromatic Connection of Graphs

open access: yesDiscussiones Mathematicae Graph Theory, 2019
A graph is said to be total-colored if all the edges and the vertices of the graph are colored. A total-coloring of a graph is a total monochromatically-connecting coloring (TMC-coloring, for short) if any two vertices of the graph are connected by a ...
Jiang Hui, Li Xueliang, Zhang Yingying
doaj   +1 more source

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

open access: yesOpen 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   +2 more
doaj   +1 more source

Inverse Problem on the Steiner Wiener Index

open access: yesDiscussiones 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

More Results on The Smallest One-Realization of A Given Set II

open access: yesDiscussiones Mathematicae Graph Theory, 2019
Let S be a finite set of positive integers. A mixed hypergraph ℋ is a onerealization of S if its feasible set is S and each entry of its chromatic spectrum is either 0 or 1.
Diao Kefeng, Lu Fuliang, Zhao Ping
doaj   +1 more source

Home - About - Disclaimer - Privacy