#include <bits/stdc++.h>
using namespace std;
using ld = long double;

int main()
{
	cout << fixed << setprecision(10);
	int N;
	ld p;
	cin >> N >> p;
	vector<ld> dp(N + 1, 1.0);
	ld res = 0;
	for (int i = 2; i <= N; i++) {
		res += dp[i];
		for (int j = i * 2; j <= N; j += i) {
			dp[j] *= (1 - p);
		}
	}
	cout << res << endl;
	return 0;
}