From a set of d-dimensional vectors for some integer d ≥ 1, we obtain a d-dot product graph by letting each vector au correspond to a vertex u and by adding an edge between two vertices u and v if and only if their dot product au · av ≥ t, for some fixed, positive threshold t. Dot product graphs can be used to model social networks. To understand the position of d-dot product graphs in the land...

The eccentricity of a vertex $v$ is the maximum distance between $v$ and anyother vertex. A vertex with maximum eccentricity is called a peripheral vertex.The peripheral Wiener index $ PW(G)$ of a graph $G$ is defined as the sum ofthe distances between all pairs of peripheral vertices of $G.$ In this paper, weinitiate the study of the peripheral Wiener index and we investigate its basicproperti...

let $g$ be a connected graph. the multiplicative zagreb eccentricity indices of $g$ are defined respectively as ${bf pi}_1^*(g)=prod_{vin v(g)}varepsilon_g^2(v)$ and ${bf pi}_2^*(g)=prod_{uvin e(g)}varepsilon_g(u)varepsilon_g(v)$, where $varepsilon_g(v)$ is the eccentricity of vertex $v$ in graph $g$ and $varepsilon_g^2(v)=(varepsilon_g(v))^2$. in this paper, we present some bounds of the multi...

let $a = (a_{i,j})_{1 leq i,j leq n}$ be an $n times n$ matrixwhere $n geq 2$. let $dt(a)$, its second immanant be the immanant corresponding to the partition $lambda_2 = 2,1^{n-2}$. let $g$ be a connected graph with blocks $b_1, b_2, ldots b_p$ and with$q$-exponential distance matrix $ed_g$. we given an explicitformula for $dt(ed_g)$ which shows that $dt(ed_g)$ is independent of the manner in ...

In this paper we present an algorithm and prove the existence of graph labelings such as Z 3 -magic, Cordial, total cordial, E-cordial, total E-cordial, Product cordial, total product cordial, Product E-cordial, total product E-cordial labelings for the Competition graph of the Cayley digraphs associated with the diheadral group D n . AMS SUBJECT CLASSIFICATION: 05C78.

 Let $R$ be an associative ring with identity and $Z^*(R)$ be its set of non-zero zero divisors.  The zero-divisor graph of $R$, denoted by $Gamma(R)$, is the graph whose vertices are the non-zero  zero-divisors of  $R$, and two distinct vertices $r$ and $s$ are adjacent if and only if $rs=0$ or $sr=0$.  In this paper, we bring some results about undirected zero-divisor graph of a monoid ring o...

The product graph B ∗ F of graphs B and F is an interesting model in the design of large reliable networks. Let G be a kG-edge connected graph and DE c (G) be the largest diameter of subgraphs of G obtained by deleting c < kG edges. We prove that DE a+b+1(B ? F ) ≤ DE a (F ) +DE b (B) + 1 where a < kF , and b < kB . Key–Words: product graph, edge-connectivity, edge fault-diameter, reliable inte...

Let G be a simple graph of order n and let V (G) be its vertex set. Let c = a + b √ m and c = a − b√m, where a and b are two nonzero integers and m is a positive integer such that m is not a perfect square. We say that A = [cij ] is the conjugate adjacency matrix of the graph G if cij = c for any two adjacent vertices i and j, cij = c for any two nonadjacent vertices i and j, and cij = 0 if i =...