Our framework is a programming method whose main idea consists in solving a problem statically and explicitly before taking some execution details into account. Within the framework of the methodology for constructing a program, we are often compelled to introduce intermediate values. We prove that in the case of sequential languages, and especially when they are sequence data types, those intermediates do not need to be effectively constructed. This aspect of the problem is obviously connected with efficiency. We suggest program transformation as a possible means of eliminating useless intermediates in the case of sequential languages. This paper follows [12] and aims at describing a program construction method, a set of transformations rules and their application with an example.