设x,y,z是正整数.如果x^2+y^2=z^2,则称(x,y,z)是一组Pythagoras数.运用初等方法证明了:恰有12组Pythagoras数(x,y,z)适合6(x+y+z)=xy.
Let x, y z be positive integers. If x^2+y^2=z^2, then (x, y, z) is called a Pythagoras triplet. In this paper, using some elementary methods, we prove that there exist exactly 12 Pythagoras triplets (x,y, z) satisfying 6(x+ y+ z)=xy.