Sur l'autocorrelation multiplicative de la fonction "partie fractionnaire"

A first encounter with $A(\lambda) := \int_0^{+\infty}{\lambda t}{t}t^{-2}dt.$ This text contains the detailed calculations leading to the results of our paper “Etude de l’autocorrelation multiplicative de la fonction “partie fractionnaire””, to appear in the Ramanujan Journal.