#include<iostream>
#include<vector>
#include<iomanip>

using namespace std;

int main() {
    int N; cin >> N;
    double p; cin >> p;
    vector<double> P(N+1, 1);
    for (int i=1;i<=N;i++) P[i] = P[i-1] * (1.0 - p);

    double E = 0;
    vector<int> cnt(N+1);
    for (int i=2;i<=N;i++) {
        E += P[cnt[i]];
        for (int j=i+i;j<=N;j+=i) {
            cnt[j]++;
        }
    }
    cout << fixed << setprecision(12) << E << endl;
}