在分解大数的因数时,中学代数教程中学过的一般方法不常采用。例如,应用通常的整除性的特征就不能分解数4891为因数之积。不用整除性的特征,从大家知道的欧拉的建议导出的方法就可以进行分解因数,欧拉的建议就是任意奇的自然数可表为两个自然数的平方差的形式。我们称这个方法为欧拉法。这个方法的内容归结于下。按照欧拉的建议,我们有n=x~2-y~2,这里x>y。分解右端部分为 When decomposing large numbers of factors, the general methods learned in the middle school algebra tutorials are not often used. For example, applying the usual divisibility feature can’t decompose the number 4891 to the product of the factors. Without the divisibility feature, the derivation factor can be deduced from the well-known method of Euler’s proposal. Euler’s proposal is that arbitrarily singular natural numbers can be expressed as the square difference of two natural numbers. We call this method Euler method. The content of this method boils down to the next. According to Euler’s suggestion, we have n=x~2-y~2, where x>y. The right part of the decomposition is