حمیدرضا دربیدی

The order graph of a group G, denoted by \Gamma*(G), is a graph whose vertices are non trivial proper subgroups of G and two distinct vertices H and K are adjacent if and only if |H|||K| or |K|||H| . In this paper, we study the connectivity and diameter of this graph. Also we give a relation between the order graph and prime graph of a group.