A graph is said to be symmetric if its automorphism group is transitive on its arcs. A complete classification is given of pentavalent symmetric graphs of order 24p for each prime p. It is shown that a connected pentavalent symmetric graph of order 24p exists if and only if p=2, 3, 5, 11 or 17, and up to isomorphism, there are only eleven such graphs.

A graph is called symmetric if its full automorphism group acts transitively on the set of arcs. The Cayley graph $Gamma=Cay(G,S)$ on group $G$ is said to be normal symmetric if $N_A(R(G))=R(G)rtimes Aut(G,S)$ acts transitively on the set of arcs of $Gamma$. In this paper, we classify all connected tetravalent normal symmetric Cayley graphs of order $p^2q$ where $p>q$ are prime numbers.

The connectivity of graph is a basic concept of graph theory. Since originated in seven bridges problem by Euler in 1736, the main study of graph theory unfolds on the assumption that the graph is connected. In classic graph theory, the edges and the vertices are all deterministic, and connectivity of the graph can be easily verified. However, in practical application, non-deterministic factors...

In this paper an algorithm for computing the Balaban and Randic indices of any simple connected graph was introduced. Also these indices were computed for IPR C80 fullerene isomers, Zigzag nanotubes and graphene by GAP program.