#include <bits/stdc++.h>
#define rep(i,n) for(int i=(0);i<(n);i++)

using namespace std;

typedef long long ll;
typedef unsigned long long ull;

template<class T> bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }

// pow
double pow(double a, ll b){
	if(b == 0) return 1.0;
	if(b & 1) {
		return a * pow(a, b - 1);
	} else {
	double d = pow(a, b / 2);
	return d * d;
	}
}

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);

	int n;
	double p;
	cin >> n >> p;

	vector<bool> isprime(n+1, true);
	isprime[0] = isprime[1] = false;
	vector<int> primes;
	for(int i = 2; i <= n; i++){
		if(isprime[i]) primes.push_back(i);
		for(int j = 2 * i; j <= n; j += i) isprime[j] = false;
	}

	double ans = 0.0;
	for(int i = 2; i <= n; i++){
		ll cnt = 1;
		int y = i;
		for(int x : primes){
			ll t = 1;
			while(y % x == 0){
				y /= x;
				t++;
			}
			cnt *= t;
		}

		cnt -= 2;
		ans += pow(1.0 - p, cnt);
	}

	cout << fixed << setprecision(10);
	cout << ans << endl;
}