double [] a=new double[5];
a[0] = 10;
double jg=10;
for (int i=0;i<5 ;i++ )
{
a[i] = jg;
jg = a[i] * 0.8;
}
Console.WriteLine("结果为{0}",a[4]);
原文：http://www.cnblogs.com/zzc134680/p/5411359.html