On the eigenvalues and Seidel eigenvalues of chain graphs
In this paper, we primarily focus on the eigenvalues of the adjacency matrix and Seidel matrix of chain graphs, referred to as eigenvalues and Seidel eigenvalues of these graphs, respectively. Firstly, we utilize the characteristic polynomial of ...
Sufficient conditions for k-leaf-connected graphs in terms of the first Zagreb index, the reciprocal degree distance and the forgotten topological index
For integer k ≥ 2, a graph G is called k-leaf-connected if | V ( G ) | ≥ k + 1 and given any subset S ⊆ V ( G ) with | S | = k, G always has a spanning tree T such that S is precisely the set of leaves of T. Thus a graph is 2-leaf-connected if ...
Highlights
- A sharp bound on the first Zagreb index that ensures k-leaf-connected is given.
- A sharp bound on reciprocal degree distance that ensures k-leaf-connected is given.
- A sharp bound on the forgotten topological index that ensures k-...
Independence number and spectral radius of cactus graphs
Four Color Theorem implies that the independence number of every planar graph is at least n / 4. A cactus graph is a connected planar graph whose block is either an edge or a cycle. In this paper, the lower bound for independence number of cactus ...
Cyclic edge and cyclic vertex connectivity of ( 4 , 5 , 6 )-fullerene graphs
Cyclic vertex connectivity c κ and cyclic edge connectivity c λ are two important kinds of conditional connectivity, which reflect the number of vertices or edges that can be removed before the graph is disconnected and at least two components ...
2-coupon coloring of cubic graphs containing 3-cycle or 4-cycle
A total dominating set in a graph G is a set S of vertices of G such that every vertex in G is adjacent to a vertex in S. Recently, the following question was proposed:
“Is it true that every connected cubic graph containing a 3-cycle has two ...
A value for cooperative games on simplicial complexes with a filtration
The classical Shapley value for cooperative games determines a payoff vector considering that the formation of the grand coalition is made by incorporating players one by one. Later, this method was generalized for games with restricted ...
Progress towards the 1/2-Conjecture for the domination game
The domination game is played on a graph G by two players, Dominator and Staller, who alternate in selecting vertices until each vertex in the graph G is contained in the closed neighbourhood of the set of selected vertices. Dominator’s aim is to ...
Lossless text compression by means of binary-coded ternary number representation
A lossless data compression code based on a binary-coded ternary number representation is investigated. The code is complete, universal, synchronizable, and supports a direct search in a compressed file. A simple monotonous encoding and very fast ...
Removable and forced subgraphs of graphs
A connected graph G is H-removable if H is a subgraph of G, G has at least | V ( H ) | + 2 vertices and G − V ( H ′ ) has a perfect matching for every subgraph H ′ of G isomorphic to H. So a connected graph is k K 2-removable if and only if it is ...
Vertex-minors of graphs: A survey
For a vertex v of a graph, the local complementation at v is an operation that replaces the neighborhood of v by its complement graph. Two graphs are locally equivalent if one is obtained from the other by a sequence of local complementations. A ...