AN OMEGA THEOREM ON DIFFERENCES OF TWO SQUARES, II
M. KUHLEITNER
Abstract.
Let $\rho(n)$ denote the number of pairs $(u,v)\in \N\times \Z$ with $u^2-v^2=\nomathbreak n$. Due to a formula of Sierpinski, $\rho(n)$ is closely related to the classical divisor function $d(n)$. We establish a lower bound for the remainder term in the asymptotic expansion for the Dirichlet summatory function of $\rho(n)$.
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