// コンパイラ型言語に逃げたのは私です。

import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class Main {

    public static void main(String... args) {
        Scanner sc = new Scanner(System.in);
        final int N = sc.nextInt();
        final double P = 1 - sc.nextDouble();

        double sum = 0;

        int[] A = new int[N + 1];
        Map<Integer, Double> V = new HashMap<>();
        for (int n = 2; n <= N; n++) {
            for (int m = n * 2; m <= N; m += n) {
                A[m] += 1;
            }
            sum += V.computeIfAbsent(A[n], (k) -> Math.pow(P, k));
        }

        System.out.println(sum);
    }
}