#include<bits/stdc++.h>
using namespace std;
#ifdef LOCAL_DEBUG
  #include "LOCAL_DEBUG.hpp"
#endif
#define int long long

signed main(){

  double n, p; cin >> n >> p;
  vector<double> dp(n + 1, 1);
  for(int i = 2; i <= n; i++){
    for(int j = i+i; j <= n; j+=i){
      dp[j] *= (1.0 - p);
    }
  }

  double ans = 0;
  for(int i = 2; i <= n; i++){
    ans += dp[i];
  }
  printf("%.7f\n", ans);

  return 0;
}