#include <stdio.h>
#include <math.h>

int main() {
    int n, num = 1;
    double x, ex = 1;
    scanf("%lf %d", &x, &n);
    
    while (num <= n) {
        double factorial = 1;
        int factorialnum = 1;
        
        while (factorialnum <= num) {
            factorial *= factorialnum;
            factorialnum += 1;
        }
        
        ex += pow(x, num) / factorial;
        num += 1;
    }
    
    printf("%.6lf", ex);
    
    return 0;
}