Fac

/* Write a program that, for a given two
 * integer numbers N and X,
 * calculates the sumS = 1 + 1!/X + 2!/X2 + … + N!/XN
 */

using System;

class ExpersionCalcThree
{
    static int FactorialCalc(int number)
    {
        int sum = 1;
        for (int i = 1; i <= number; i++)
        {
            sum = sum * i;
        }
        return sum;
    }
    static void Main()
    {
        double x = int.Parse(Console.ReadLine());
        double n = int.Parse(Console.ReadLine());
        double sum = 1;
        for (int i = 1; i <= n; i++)
        {
            sum = sum + FactorialCalc(i) / Math.Pow(x, i);
        }
        Console.WriteLine(sum);
    }
}