8th June Valentin Blomer<br>
    Estimates for representation numbers of quadratic forms <br>                                                    
Let f be a positive integral binary quadratic form of
discriminant -D, and let r_f(n) be the number of representations of
n by f. We give various estimates and asymptotics for the moments
\sum_{n\leq x} r_f(n)^{\beta} for all \beta >= 0 and uniformly in
D=o(x). As an application we study sums of two squareful numbers. This
is joint work with A. Granville.