In many applications, like database management systems, is very useful to have an expression to compute the cardinality of cartesian product of k sets without repeated elements; we designate this problem as T(k). The value of |T(k)| is upper-bounded by the multiplication of cardinalities of the sets. As long as we have searched, it has not been reported a general expression to compute T(k) using cardinalities of the intersections of sets, this is the main topic of this paper. Given three sets with indices {0,1,2}, Ci is the cardinality of one set, Ci,j (i<j) and Ci,j,l (i<j<l) are respectively the cardinalities of the intersections of 2 and 3 sets, then the searched formulas for T(k) are: T(1)=C0; T(2)=C0C1-C0,1; T(3)=C0C1C2-(C0,1C2+C0,2C1+C1,2C0)+2C0,1,2. In this paper, we prove formulas for computing T(k) and its specialization when a set is contained in the next sets. For this purpose, we will use concepts like partitions of the integer k in v parts, Bell numbers, Stirling numbers of the first kind and Stirling numbers of the second kind. Additionally, we present a complexity analysis for the computation of T(k).