The finite subsets of natural numbers

Abstract

The article discusses relationships between triangle and square numbers. The stress is laid upon numerical equality. A finite set of these numbers and its subsets are given by software. Finding natural numbers with a specific property is of great didactic value. This topic was included into the course of study preparing future elementary school teachers. The article deals with comparison of mathematical problem solving procedures by 1st and 4th year elementary school student teachers. The method of experiment was applied. Accessible software is used in solving more complex problems in the 4th year.