A Note on Super Connectivity of the Bouwer Graph

The Bouwer graph [Formula: see text], proposed in 1970, is defined for every triple [Formula: see text] of integers greater than [Formula: see text] with [Formula: see text]. It has many good properties, such as vertex-transitive and edge-transitive. Conder and Žitnik used a cycle-counting argument to prove that almost all of the Bouwer graphs are half-arc-transitive in 2016. In this paper, by exploring the structure properties of [Formula: see text], we investigate some reliability measures, including super connectivity and super-edge connectivity, and show that the super connectivity and super-edge connectivity of the Bouwer graph are both [Formula: see text] for [Formula: see text], [Formula: see text] and [Formula: see text].

The (n,k)-Modified-Bubble-Sort Graph: A Generalized Modified-Bubble-Sort Graph

In this paper, we present a new interconnection topology, called the[Formula: see text]-modified-bubble-sort graph, which is a generalization of the modified-bubble-sort graph. Additionally, we show many of its properties, such as its hierarchical structure, vertex transitivity, connectivity, edge-connectivity, super connectivity and super edge-connectivity. The [Formula: see text]-modified-bubble-sort graph presents more flexibility than the modified-bubble-sort graph in terms of its major design properties.

The super-connectivity of odd graphs and of their Kronecker double cover

The study of connectivity parameters forms an integral part of the research conducted in establishing the fault tolerance of networks. A number of variations on the classical notion of connectivity have been proposed and studied. In particular, the super--connectivity asks for the minimum number of vertices that need to be deleted from a graph in order to disconnect the graph without creating isolated vertices. In this work, we determine this value for two closely related families of graphs which are considered as good models for networks, namely the odd graphs and their Kronecker double cover. The odd graphs are constructed by taking all possible subsets of size $k$ from the set of integers $\{1,\ldots,2k+1\}$ as vertices, and defining two vertices to be adjacent if the corresponding $k$-subsets are disjoint; these correspond to the Kneser graphs $KG(2k+1,k)$. The Kronecker double cover of a graph $G$ is formed by taking the Kronecker product of $G$ with the complete graph on two vertices; in the case when $G$ is $KG(2k+1,k)$, the Kronecker double cover is the bipartite Kneser graph $H(2k+1,k)$. We show that in both instances, the super--connectivity is equal to $2k$.

Super Connectivity of Erdős-Rényi Graphs

The super connectivity κ ′ ( G ) of a graph G is the minimum cardinality of vertices, if any, whose deletion results in a disconnected graph that contains no isolated vertex. G is said to be r-super connected if κ ′ ( G ) ≥ r . In this note, we establish some asymptotic almost sure results on r-super connectedness for classical Erdős–Rényi random graphs as the number of nodes tends to infinity. The known results for r-connectedness are extended to r-super connectedness by pairing off vertices and estimating the probability of disconnecting the graph that one gets by identifying the two vertices of each pair.