#include <bits/stdc++.h>
using namespace std;
template <class T>
inline T _sq(T a) {
  return a * a;
}
template <class T>
inline T _sqrt(T a) {
  return (T)sqrt((double)a);
}
template <class T, class X>
inline T _pow(T a, X y) {
  T z = 1;
  for (int i = 1; i <= y; i++) {
    z *= a;
  }
  return z;
}
template <class T>
inline T _gcd(T a, T b) {
  a = abs(a);
  b = abs(b);
  if (!b) return a;
  return _gcd(b, a % b);
}
template <class T>
inline T _lcm(T a, T b) {
  a = abs(a);
  b = abs(b);
  return (a / _gcd(a, b)) * b;
}
template <class T>
inline T _extended(T a, T b, T &x, T &y) {
  a = abs(a);
  b = abs(b);
  T g, x1, y1;
  if (!b) {
    x = 1;
    y = 0;
    g = a;
    return g;
  }
  g = _extended(b, a % b, x1, y1);
  x = y1;
  y = x1 - (a / b) * y1;
  return g;
}
template <class T, class X>
inline bool getbit(T a, X i) {
  T t = 1;
  return ((a & (t << i)) > 0);
}
template <class T, class X>
inline T setbit(T a, X i) {
  T t = 1;
  return (a | (t << i));
}
template <class T, class X>
inline T resetbit(T a, X i) {
  T t = 1;
  return (a & (~(t << i)));
}
template <class T, class X>
inline T togglebit(T a, X i) {
  T t = 1;
  return (a ^ (t << i));
}
template <class T>
void pv(T v) {
  for (int i = 0; i < ((int)v.size()); i++) cout << v[i] << " ";
  cout << endl;
}
template <class T, class X>
inline T _bigmod(T n, X m) {
  unsigned long long ret = 1, a = n % 1000000007;
  while (m) {
    if (m & 1) ret = (ret * a) % 1000000007;
    m >>= 1;
    a = (a * a) % 1000000007;
  }
  ret %= 1000000007;
  return (T)ret;
}
template <class T>
inline T _modinv(T n) {
  return _bigmod(n, 1000000007 - 2);
}
double _pow(double x, long long n) {
  double ret = 1.0;
  while (n) {
    if (n & 1) ret *= x;
    n >>= 1;
    x *= x;
  }
  return ret;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  long long n;
  double m, ans;
  cin >> m >> n;
  ans = m;
  for (int i = 1; i <= m - 1; i++) {
    ans -= _pow((double)i / m, n);
  }
  cout << setprecision(12) << fixed << ans << endl;
  return 0;
}
