Paolo Boieri* (Italy), boieri@calvino.polito.it Exploring sequences with DERIVE Sequences usually are not treated as deeply as functions in Calculus courses. However, sequences show many interesting properties that do not appear in elementary presentation of functions. This paper describes a teaching unit that, using DERIVE, helps the student of a first year University course in Calculus to discover and understand some features of the behaviour of a sequence, defined as a function of n or by recursion. Several computer experimentations introduce the problem of understanding the idea of how fast a sequence grows for n going to infinity and what is the meaning of comparing sequences behaviour at infinity.