Maximum number of symmetric extensions in the random graph

Abstract

It is known that after an appropriate rescaling the maximum degree of the binomial random graph converges in distribution to a Gumbel random variable. The same holds true for the maximum number of common neighbours of a $k$-vertex set, and for the maximum number of $s$-cliques sharing a single vertex. Can these results be generalised to the maximum number of extensions of a $k$-vertex set for any given way of extending of a $k$-vertex set by an $s$-vertex set? In this paper, we generalise the above mentioned results to a class of ``symmetric extensions'' and show that the limit distribution is not necessarily from the Gumbel family.