The clustering coefficient of a scale-free random graph

We consider a random graph process in which, at each time step, a new vertex is added with m out-neighbours, chosen with probabilities proportional to their degree plus a strictly positive constant. We show that the expectation of the clustering coefficient of the graph process is asymptotically proportional to log n/n. Bollobas and Riordan have previously shown that when the constant is zero, the same expectation is asymptotically proportional to (log n)(2)/n. (C) 2011 Elsevier B.V. All rights reserved.