#include<bits/stdc++.h>

 #define LL long long

 #define LD long double

 #define  N 100005

 using namespace std;

 inline int ra()

 {

     int x=,f=; char ch=getchar();

     while (ch<'' || ch>'') {if (ch=='-') f=-; ch=getchar();}

     while (ch>='' && ch<='') {x=x*+ch-''; ch=getchar();}

     return x*f;

 }

 double ksm(double a, int p)

 {

     double sum=;

     for (;p;p>>=,a*=a)

         if (p&)

             sum*=a;

     return sum;

 }

 int main()

 {

     int n=ra(),m=ra();

     double ans=;

     for (int i=; i<=n; i++)

         ans+=(double)i*(ksm((double)i/n,m)-ksm((double)(i-)/n,m));

     printf("%.12lf",ans);

     return ;

 }