#include <bits/stdc++.h>


int main() {

  double v[1000100];
  double p;
  double ans = 0.0;
  long N;

  std::cin >> N >> p;
  
  for(int i = 2; i <= N; ++i) {
    v[i] = 1.0;
  }

  for(int i = 2; i <= N; ++i) {
    ans += v[i];
    for(int j = i + i; j <= N; j += i) {
      v[j] *= (1-p);
    }
  }

  printf("%.10lf\n", ans);
  
  return 0;
}