import std.stdio, std.conv, std.math, std.string, std.range, std.array,
       std.algorithm;

double[] is_prime;

void Eratosthenes(long lim, double q){
  is_prime[] = 1.0;
  is_prime[0] = 0.0;
  is_prime[1] = 0.0;
  for(long p=2; p<=lim; p++) {
    for(long k=2*p; k<=lim; k+=p) is_prime[k] *= q;
  }
}

void main(){
  auto buf = readln().strip().split();
  immutable N = buf[0].to!int;
  immutable p = buf[1].to!double;

  is_prime.length = N + 5;

  Eratosthenes(N, 1-p);

  double ans = 0;
  foreach(immutable i; 2 .. N+1) {
    ans += is_prime[i];
  }

  writefln("%.10f", ans);
}