using System;
class jiecheng
{
	static void Main()
	{
		long i=1;
		long j=1;
		long m=0;
		for (j=1;j<=20;j++)
		{

			i=i*j;

			Console.WriteLine(i);

			m+=i;

		}
		Console.WriteLine("所求的总和是:"+m);
		System.Threading.Thread.Sleep(80000000);
	}
}