#include <bits/stdc++.h>

using namespace std;

#ifdef LOCAL
#include "debug.hpp"
#else
#define debug(...) 1
#endif

vector<int> sieve(int n) {
    vector<int> min_factor(n + 1);
    for (int i = 1; i <= n; i++) {
        min_factor[i] = i;
    }

    for (int i = 2; i * i <= n; i++) {
        if (min_factor[i] == i) {
            for (int j = i + i; j <= n; j += i) {
                if (min_factor[j] > i) {
                    min_factor[j] = i;
                }
            }
        }
    }

    return min_factor;
}

map<int, int> factor(vector<int> &min_factor, int m) {
    map<int, int> ret;
    while (m > 1) {
        ret[min_factor[m]]++;
        m /= min_factor[m];
    }
    return ret;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n;
    cin >> n;
    auto v = sieve(n);
    double p;
    cin >> p;
    double ans = 0;
    for (int i = 2; i <= n; i++) {
        auto mp = factor(v, i);
        int cnt = 1;
        for (auto [x, y] : mp) {
            cnt *= (y + 1);
        }
        ans += pow(1 - p, cnt - 2);
    }
    cout << fixed << setprecision(15) << ans << '\n';
}