p38e11

#include <iostream>
using namespace std;

double f (int x, int n, int k)
{
	if(k == n) return (double)(k + x);
	int i = k;
	return i + x/f(x,n, ++k);
}

int main(void)
{
	int x,n;
	cin >> x >> n;
	cout << f(x, n, 0);
}